<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:8ef8b9a0-38f7-49e9-b337-07b78536219e,g:f9e3b692-4ced-4a7a-991d-7b4a5f786847-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.marqeta.com/role/CoverPage" xlink:type="simple" xlink:href="mq-20250930.xsd#CoverPage"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CoverPage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_74c432e5-bf7f-42b4-9464-a8bb20d47970" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntitiesTable_74c432e5-bf7f-42b4-9464-a8bb20d47970" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_72faddc0-b6aa-4124-a186-2acf717037af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_74c432e5-bf7f-42b4-9464-a8bb20d47970" xlink:to="loc_us-gaap_StatementClassOfStockAxis_72faddc0-b6aa-4124-a186-2acf717037af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_72faddc0-b6aa-4124-a186-2acf717037af_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_72faddc0-b6aa-4124-a186-2acf717037af" xlink:to="loc_us-gaap_ClassOfStockDomain_72faddc0-b6aa-4124-a186-2acf717037af_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_648e3e16-25d8-4965-9615-c982574ad993" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_72faddc0-b6aa-4124-a186-2acf717037af" xlink:to="loc_us-gaap_ClassOfStockDomain_648e3e16-25d8-4965-9615-c982574ad993" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_b5750b1e-859f-47c6-9511-be8bf3f7f8e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_648e3e16-25d8-4965-9615-c982574ad993" xlink:to="loc_us-gaap_CommonClassAMember_b5750b1e-859f-47c6-9511-be8bf3f7f8e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_b679870d-3964-4824-86f8-9ad92d32d2aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_648e3e16-25d8-4965-9615-c982574ad993" xlink:to="loc_us-gaap_CommonClassBMember_b679870d-3964-4824-86f8-9ad92d32d2aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_178db937-b7e2-4998-84a3-b901ed171d0d" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentType_178db937-b7e2-4998-84a3-b901ed171d0d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentQuarterlyReport_bccd135e-2c2d-4bd4-83fe-5c6aa8030faa" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentQuarterlyReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentQuarterlyReport_bccd135e-2c2d-4bd4-83fe-5c6aa8030faa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_170cfd2b-0f82-4e81-8bc0-36554e2318b3" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentPeriodEndDate_170cfd2b-0f82-4e81-8bc0-36554e2318b3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport_b746b907-76d3-4e8f-a784-e9575b807170" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentTransitionReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentTransitionReport_b746b907-76d3-4e8f-a784-e9575b807170" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_b794de57-50ac-4bb4-abf6-214f30d07c75" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityFileNumber_b794de57-50ac-4bb4-abf6-214f30d07c75" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_0c95d7a3-1f05-47cc-a52e-5e2554ef3e2b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityRegistrantName_0c95d7a3-1f05-47cc-a52e-5e2554ef3e2b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_e1e38b9b-4327-4dd4-a96f-7bdc486a5213" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityIncorporationStateCountryCode_e1e38b9b-4327-4dd4-a96f-7bdc486a5213" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_a146ca7f-9ef0-4603-8901-05800c0ce5a8" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityTaxIdentificationNumber_a146ca7f-9ef0-4603-8901-05800c0ce5a8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_49d5b57c-3fbc-41c2-9cb1-218a6f746f58" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityAddressAddressLine1_49d5b57c-3fbc-41c2-9cb1-218a6f746f58" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_3e878e91-be61-4325-9964-9f035bd9c4bc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityAddressAddressLine2_3e878e91-be61-4325-9964-9f035bd9c4bc" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_3d34176c-a70f-4eda-98c4-321153fc7d0b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityAddressCityOrTown_3d34176c-a70f-4eda-98c4-321153fc7d0b" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_fa7ef61e-039f-437c-918f-3485d972605f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityAddressStateOrProvince_fa7ef61e-039f-437c-918f-3485d972605f" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_ca1578fd-175f-44d3-96c4-144ba99077e3" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityAddressPostalZipCode_ca1578fd-175f-44d3-96c4-144ba99077e3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_d01667ee-173a-4c1a-90c8-44b3cb35272b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_CityAreaCode_d01667ee-173a-4c1a-90c8-44b3cb35272b" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_28201f0f-b4e5-483f-b85d-79b7301d6398" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_LocalPhoneNumber_28201f0f-b4e5-483f-b85d-79b7301d6398" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_3ecf4e46-57a9-4b36-b3df-88bcd8e98d2e" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_Security12bTitle_3ecf4e46-57a9-4b36-b3df-88bcd8e98d2e" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_6ea22ecb-97e1-474e-ba96-0613f860fc0f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_TradingSymbol_6ea22ecb-97e1-474e-ba96-0613f860fc0f" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_aaf4cfe3-b292-4c35-a30b-ec415b88ae81" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_SecurityExchangeName_aaf4cfe3-b292-4c35-a30b-ec415b88ae81" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus_549e0a27-f76f-4974-aa5f-9eb6b8703c8c" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCurrentReportingStatus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityCurrentReportingStatus_549e0a27-f76f-4974-aa5f-9eb6b8703c8c" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent_2527cc21-2010-4cae-8d70-deea9dc5d91f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityInteractiveDataCurrent_2527cc21-2010-4cae-8d70-deea9dc5d91f" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory_bd9c3dd3-0583-415b-836e-330526f8bc98" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFilerCategory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityFilerCategory_bd9c3dd3-0583-415b-836e-330526f8bc98" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_b7431735-deaa-44da-aef3-c35c468d72ec" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntitySmallBusiness_b7431735-deaa-44da-aef3-c35c468d72ec" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_1e30ccec-7098-47e9-9e25-c9fcae740c57" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityEmergingGrowthCompany_1e30ccec-7098-47e9-9e25-c9fcae740c57" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany_7af4bd27-7981-40ec-8e46-9ff1b74fc535" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityShellCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityShellCompany_7af4bd27-7981-40ec-8e46-9ff1b74fc535" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_26beb5a8-b2ca-478e-8b5e-89dd7791bfd0" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_26beb5a8-b2ca-478e-8b5e-89dd7791bfd0" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_096a8bd4-f9b3-4a63-a7a3-07e3f35d1669" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_EntityCentralIndexKey_096a8bd4-f9b3-4a63-a7a3-07e3f35d1669" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate_3b2d5fc7-157c-4a8e-a65a-a34bd13529fb" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_CurrentFiscalYearEndDate_3b2d5fc7-157c-4a8e-a65a-a34bd13529fb" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus_df21f1ef-77c2-4220-9d67-0ab759f3eee9" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalYearFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentFiscalYearFocus_df21f1ef-77c2-4220-9d67-0ab759f3eee9" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_d5013e34-1908-42ad-a055-6c5325db91fc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_AmendmentFlag_d5013e34-1908-42ad-a055-6c5325db91fc" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus_d42e348a-6fbe-4f23-9894-71ac42207f05" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_5b8f05d5-be2b-4feb-9c6f-c09761e91ac1" xlink:to="loc_dei_DocumentFiscalPeriodFocus_d42e348a-6fbe-4f23-9894-71ac42207f05" xlink:type="arc" order="29"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/CondensedConsolidatedBalanceSheetsParentheticals" xlink:type="simple" xlink:href="mq-20250930.xsd#CondensedConsolidatedBalanceSheetsParentheticals"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CondensedConsolidatedBalanceSheetsParentheticals" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_f5684446-c0d1-4bd6-999f-a95e3f6f8dec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_StatementTable_f5684446-c0d1-4bd6-999f-a95e3f6f8dec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_ae6e5fbc-fd13-49bb-a618-d55d9881d636" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f5684446-c0d1-4bd6-999f-a95e3f6f8dec" xlink:to="loc_us-gaap_StatementClassOfStockAxis_ae6e5fbc-fd13-49bb-a618-d55d9881d636" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_ae6e5fbc-fd13-49bb-a618-d55d9881d636_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_ae6e5fbc-fd13-49bb-a618-d55d9881d636" xlink:to="loc_us-gaap_ClassOfStockDomain_ae6e5fbc-fd13-49bb-a618-d55d9881d636_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_b81daacf-bb4b-4b8c-834a-04e1f1b804f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_ae6e5fbc-fd13-49bb-a618-d55d9881d636" xlink:to="loc_us-gaap_ClassOfStockDomain_b81daacf-bb4b-4b8c-834a-04e1f1b804f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_6d1fef0e-b0b9-4ca7-ac74-b750ea954950" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_b81daacf-bb4b-4b8c-834a-04e1f1b804f4" xlink:to="loc_us-gaap_CommonClassAMember_6d1fef0e-b0b9-4ca7-ac74-b750ea954950" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_d0e9163f-ca71-4a67-890c-67fcde001285" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_b81daacf-bb4b-4b8c-834a-04e1f1b804f4" xlink:to="loc_us-gaap_CommonClassBMember_d0e9163f-ca71-4a67-890c-67fcde001285" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_16703ab0-de34-4a2d-bfe0-a24f7b1e3b9b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_16703ab0-de34-4a2d-bfe0-a24f7b1e3b9b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_3070411f-2403-4af5-805e-576d43445c4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_3070411f-2403-4af5-805e-576d43445c4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesIssued_7c721b8a-3b90-4222-869c-46bcbcefd0f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_PreferredStockSharesIssued_7c721b8a-3b90-4222-869c-46bcbcefd0f1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_6cd66a71-0269-4668-a3ec-ba54ee6aa7af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_6cd66a71-0269-4668-a3ec-ba54ee6aa7af" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_e2c4943e-81b0-4351-a36d-bcc3db9ac844" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_e2c4943e-81b0-4351-a36d-bcc3db9ac844" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_b219732e-cfd8-41f8-9a53-eff885e2e8d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_b219732e-cfd8-41f8-9a53-eff885e2e8d2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_0bb5007b-c304-4b8f-a6bb-01d148996c65" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_CommonStockSharesIssued_0bb5007b-c304-4b8f-a6bb-01d148996c65" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_a7708737-001d-4b7e-bf3e-744dbeb85988" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_2ea8f2bd-368c-484b-9de8-a804ca308a69" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_a7708737-001d-4b7e-bf3e-744dbeb85988" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="simple" xlink:href="mq-20250930.xsd#CondensedConsolidatedStatementsofStockholdersEquity"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_66f02726-02ee-4aee-86c2-f6a44d1bfae2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_9535b9d5-9e74-4f3c-91f8-735108aca786" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_66f02726-02ee-4aee-86c2-f6a44d1bfae2" xlink:to="loc_us-gaap_StatementTable_9535b9d5-9e74-4f3c-91f8-735108aca786" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_27d8de3f-c2fd-479a-8afa-08a66d1c41d7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_9535b9d5-9e74-4f3c-91f8-735108aca786" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_27d8de3f-c2fd-479a-8afa-08a66d1c41d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_27d8de3f-c2fd-479a-8afa-08a66d1c41d7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_27d8de3f-c2fd-479a-8afa-08a66d1c41d7" xlink:to="loc_us-gaap_EquityComponentDomain_27d8de3f-c2fd-479a-8afa-08a66d1c41d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_27d8de3f-c2fd-479a-8afa-08a66d1c41d7" xlink:to="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_471a4af6-852d-47ce-addb-2e824610b367" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:to="loc_us-gaap_CommonStockMember_471a4af6-852d-47ce-addb-2e824610b367" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_f1492f2c-20c7-4de1-92f0-2fcce6a1b72a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_f1492f2c-20c7-4de1-92f0-2fcce6a1b72a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_e114a908-d8bc-4464-bccb-dbab515b5b42" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_e114a908-d8bc-4464-bccb-dbab515b5b42" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_3e5c2d08-0b44-444e-9e3f-f73b24ceb9ff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_32d8acba-6fe4-4ab2-bf71-950c671e85d4" xlink:to="loc_us-gaap_RetainedEarningsMember_3e5c2d08-0b44-444e-9e3f-f73b24ceb9ff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_66f02726-02ee-4aee-86c2-f6a44d1bfae2" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_25959ab1-3c01-45ce-a27c-8a8796987281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_25959ab1-3c01-45ce-a27c-8a8796987281" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_e67057ba-d87f-4d6f-af91-d8e4ae9daa96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockholdersEquity_e67057ba-d87f-4d6f-af91-d8e4ae9daa96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_548e8752-79a0-4910-9021-10ee72ba401e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_548e8752-79a0-4910-9021-10ee72ba401e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_fa29bdd4-11a5-4409-b517-59633c400b23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_fa29bdd4-11a5-4409-b517-59633c400b23" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_b428b12d-b6fb-4675-8f34-283fa3568f6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_b428b12d-b6fb-4675-8f34-283fa3568f6b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_23d769c7-50ec-4b83-a648-e8ba3564dda0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_23d769c7-50ec-4b83-a648-e8ba3564dda0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesOther_044d987d-92a9-45df-8da2-76b520997b32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesOther_044d987d-92a9-45df-8da2-76b520997b32" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueOther_a84be1fc-8ad5-46e3-a1cc-8e204dd53ff3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueOther_a84be1fc-8ad5-46e3-a1cc-8e204dd53ff3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrants_0f5325d9-9600-47a4-97e6-4a29dea5c353" xlink:href="mq-20250930.xsd#mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrants_0f5325d9-9600-47a4-97e6-4a29dea5c353" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrantsAmount_bf47696f-c8f4-4246-9a5a-34867d2246b6" xlink:href="mq-20250930.xsd#mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrantsAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_mq_IssuanceOfCommonStockUponExerciseOfCommonStockWarrantsAmount_bf47696f-c8f4-4246-9a5a-34867d2246b6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued_3bd4d94f-eb71-49ce-a1f2-902e80781451" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued_3bd4d94f-eb71-49ce-a1f2-902e80781451" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition_6de38b32-8a78-4f61-b8f9-229c48948f6d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition_6de38b32-8a78-4f61-b8f9-229c48948f6d" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_ExecutiveChairmanLongTermPerformanceAward_93bbb23a-509d-4f86-9814-828e12183670" xlink:href="mq-20250930.xsd#mq_ExecutiveChairmanLongTermPerformanceAward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_mq_ExecutiveChairmanLongTermPerformanceAward_93bbb23a-509d-4f86-9814-828e12183670" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_ece88600-337d-4499-93eb-b5f505eebaac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_ece88600-337d-4499-93eb-b5f505eebaac" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_f8aef2f9-f4c3-4802-8b35-3de919d201ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_f8aef2f9-f4c3-4802-8b35-3de919d201ee" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_7a13d670-726d-403d-9efc-10ebe5610c23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_7a13d670-726d-403d-9efc-10ebe5610c23" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_ef34d09e-e4ae-4e4c-b4bb-6e324ea0dd0e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_2116c4f7-b42e-49a7-886d-96eccaf9c6d1" xlink:to="loc_us-gaap_NetIncomeLoss_ef34d09e-e4ae-4e4c-b4bb-6e324ea0dd0e" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_17105ad8-d794-41e3-85cd-5b2325302087" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_cf008228-0490-44de-81cf-e0c90c8c9221" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/SummaryofSignificantAccountingPoliciesDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#SummaryofSignificantAccountingPoliciesDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/SummaryofSignificantAccountingPoliciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfProductInformationTable_afc95edd-63cc-465f-861f-8346011123f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfProductInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:to="loc_us-gaap_ScheduleOfProductInformationTable_afc95edd-63cc-465f-861f-8346011123f9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_5ab8d259-d782-4517-b0ba-f19c5fe803fa" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_afc95edd-63cc-465f-861f-8346011123f9" xlink:to="loc_srt_RangeAxis_5ab8d259-d782-4517-b0ba-f19c5fe803fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_5ab8d259-d782-4517-b0ba-f19c5fe803fa_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_5ab8d259-d782-4517-b0ba-f19c5fe803fa" xlink:to="loc_srt_RangeMember_5ab8d259-d782-4517-b0ba-f19c5fe803fa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_3a3cbbd8-5e12-4bad-86c7-3eeb522496a8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_5ab8d259-d782-4517-b0ba-f19c5fe803fa" xlink:to="loc_srt_RangeMember_3a3cbbd8-5e12-4bad-86c7-3eeb522496a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_e06f4e51-b73a-477f-a114-0db07d8c9fe3" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_3a3cbbd8-5e12-4bad-86c7-3eeb522496a8" xlink:to="loc_srt_MinimumMember_e06f4e51-b73a-477f-a114-0db07d8c9fe3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_f8238b82-1a49-4ea9-a00f-0c19ba3f580d" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_3a3cbbd8-5e12-4bad-86c7-3eeb522496a8" xlink:to="loc_srt_MaximumMember_f8238b82-1a49-4ea9-a00f-0c19ba3f580d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RevenueFromContractWithCustomerCardNetworkFeesRecognizedFromChangeInAccountingPolicy_e996f3b2-49b0-43f7-8dd8-4fd83458fb59" xlink:href="mq-20250930.xsd#mq_RevenueFromContractWithCustomerCardNetworkFeesRecognizedFromChangeInAccountingPolicy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:to="loc_mq_RevenueFromContractWithCustomerCardNetworkFeesRecognizedFromChangeInAccountingPolicy_e996f3b2-49b0-43f7-8dd8-4fd83458fb59" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RevenueFromContractWithCustomerCardNetworkTerm_a362a107-8dac-41e5-8bf4-95faf33cd96e" xlink:href="mq-20250930.xsd#mq_RevenueFromContractWithCustomerCardNetworkTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:to="loc_mq_RevenueFromContractWithCustomerCardNetworkTerm_a362a107-8dac-41e5-8bf4-95faf33cd96e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RevenueFromContractWithCustomerCardNetworkRenewalTerm_ff4023a8-ae00-4266-a639-b3f2ba28f9d1" xlink:href="mq-20250930.xsd#mq_RevenueFromContractWithCustomerCardNetworkRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:to="loc_mq_RevenueFromContractWithCustomerCardNetworkRenewalTerm_ff4023a8-ae00-4266-a639-b3f2ba28f9d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_ReclassificationOfRestrictedCashToCashAndCashEquivalents_9f4b6715-d1b0-4abd-b10e-28f37c60472b" xlink:href="mq-20250930.xsd#mq_ReclassificationOfRestrictedCashToCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_174d696b-d0f0-4b60-8a12-1a7f93ee0b51" xlink:to="loc_mq_ReclassificationOfRestrictedCashToCashAndCashEquivalents_9f4b6715-d1b0-4abd-b10e-28f37c60472b" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/RevenueScheduleofDisaggregationofRevenueDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#RevenueScheduleofDisaggregationofRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/RevenueScheduleofDisaggregationofRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_b130d1c7-026f-459c-9611-126799f8b899" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_8d31f265-b861-4ec6-9117-8826a65196dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_b130d1c7-026f-459c-9611-126799f8b899" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_8d31f265-b861-4ec6-9117-8826a65196dd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_263ced03-08ed-41eb-8379-716c9ac242f7" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_8d31f265-b861-4ec6-9117-8826a65196dd" xlink:to="loc_srt_ProductOrServiceAxis_263ced03-08ed-41eb-8379-716c9ac242f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_263ced03-08ed-41eb-8379-716c9ac242f7_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_263ced03-08ed-41eb-8379-716c9ac242f7" xlink:to="loc_srt_ProductsAndServicesDomain_263ced03-08ed-41eb-8379-716c9ac242f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_2f3e9f61-32b0-4bc3-ab82-7bcf5949a8bc" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_263ced03-08ed-41eb-8379-716c9ac242f7" xlink:to="loc_srt_ProductsAndServicesDomain_2f3e9f61-32b0-4bc3-ab82-7bcf5949a8bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_PlatformServiceRevenueNetMember_17082c3e-4d39-4293-879d-4c5af3086550" xlink:href="mq-20250930.xsd#mq_PlatformServiceRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_2f3e9f61-32b0-4bc3-ab82-7bcf5949a8bc" xlink:to="loc_mq_PlatformServiceRevenueNetMember_17082c3e-4d39-4293-879d-4c5af3086550" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_OtherServicesRevenueMember_03f3057e-a58f-457e-8d95-892d8cd7b77d" xlink:href="mq-20250930.xsd#mq_OtherServicesRevenueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_2f3e9f61-32b0-4bc3-ab82-7bcf5949a8bc" xlink:to="loc_mq_OtherServicesRevenueMember_03f3057e-a58f-457e-8d95-892d8cd7b77d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_e71b71e3-8b74-488f-8d3b-5c25b0ff59de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_b130d1c7-026f-459c-9611-126799f8b899" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_e71b71e3-8b74-488f-8d3b-5c25b0ff59de" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/RevenueScheduleofContractAssetsandDeferredRevenueDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#RevenueScheduleofContractAssetsandDeferredRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/RevenueScheduleofContractAssetsandDeferredRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_31d2b0cf-96fe-4e6b-b049-83f56aebd147" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_31d2b0cf-96fe-4e6b-b049-83f56aebd147" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_58bbb4bd-f651-4bcd-82a5-d037d578f6ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_31d2b0cf-96fe-4e6b-b049-83f56aebd147" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_58bbb4bd-f651-4bcd-82a5-d037d578f6ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_58bbb4bd-f651-4bcd-82a5-d037d578f6ac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_58bbb4bd-f651-4bcd-82a5-d037d578f6ac" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_58bbb4bd-f651-4bcd-82a5-d037d578f6ac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_58bbb4bd-f651-4bcd-82a5-d037d578f6ac" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_88a270d8-e8d2-4023-b982-d1fe717a0aa3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:to="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_88a270d8-e8d2-4023-b982-d1fe717a0aa3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsMember_128a0805-5ca1-491d-9a85-65defc1348fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:to="loc_us-gaap_OtherAssetsMember_128a0805-5ca1-491d-9a85-65defc1348fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesMember_bed3a394-5cc8-41cf-929c-3e2761dd987e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:to="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesMember_bed3a394-5cc8-41cf-929c-3e2761dd987e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesMember_755ba476-dd6b-4eeb-a06b-b4ac11ec221b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_4807d788-7b9b-4fa8-99d6-4b115df02ca9" xlink:to="loc_us-gaap_OtherLiabilitiesMember_755ba476-dd6b-4eeb-a06b-b4ac11ec221b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_5cfec20a-349f-47d5-a849-e7ebcf06aac1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetCurrent_5cfec20a-349f-47d5-a849-e7ebcf06aac1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetNoncurrent_3046d53f-da94-4b65-9f25-ee3e0085fa8a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetNoncurrent_3046d53f-da94-4b65-9f25-ee3e0085fa8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNet_4465f0da-3917-4581-9cfd-42e2521064e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerAssetNet_4465f0da-3917-4581-9cfd-42e2521064e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_ec7ea003-cb10-458b-9387-c56a8bf7221c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityCurrent_ec7ea003-cb10-458b-9387-c56a8bf7221c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_04e910d8-a295-43ab-8ecc-6d3f10ccf548" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_04e910d8-a295-43ab-8ecc-6d3f10ccf548" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiability_f507ada7-26b6-41ad-86d5-2915cf4095b7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_ecb1ebd2-9e12-4f24-8efb-0f143b956c37" xlink:to="loc_us-gaap_ContractWithCustomerLiability_f507ada7-26b6-41ad-86d5-2915cf4095b7" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/RevenueRevenueRemainingPerformanceObligationsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#RevenueRevenueRemainingPerformanceObligationsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/RevenueRevenueRemainingPerformanceObligationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_de15718f-1c13-40d5-afc0-8b3f3b2a16f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_de15718f-1c13-40d5-afc0-8b3f3b2a16f6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_45a5e809-16d0-4cb3-a497-421e4215dca0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_de15718f-1c13-40d5-afc0-8b3f3b2a16f6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_45a5e809-16d0-4cb3-a497-421e4215dca0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_4e8086f8-9470-449e-a82e-141a731bf0a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_4e8086f8-9470-449e-a82e-141a731bf0a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_5d191851-c38c-4c3a-b147-8682018ccbc5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_5d191851-c38c-4c3a-b147-8682018ccbc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_955c087a-a1eb-475f-9b13-f5a6691f6d3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_955c087a-a1eb-475f-9b13-f5a6691f6d3b" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/RevenueRevenueRemainingPerformanceObligationsDetails_1" xlink:type="simple" xlink:href="mq-20250930.xsd#RevenueRevenueRemainingPerformanceObligationsDetails_1"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/RevenueRevenueRemainingPerformanceObligationsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_de15718f-1c13-40d5-afc0-8b3f3b2a16f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_de15718f-1c13-40d5-afc0-8b3f3b2a16f6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_4e8086f8-9470-449e-a82e-141a731bf0a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_4e8086f8-9470-449e-a82e-141a731bf0a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_5d191851-c38c-4c3a-b147-8682018ccbc5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_5d191851-c38c-4c3a-b147-8682018ccbc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_955c087a-a1eb-475f-9b13-f5a6691f6d3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_28fe1b32-4951-49fc-a21d-b93736a2c05d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_955c087a-a1eb-475f-9b13-f5a6691f6d3b" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/BusinessCombinationsScheduleofPurchasePriceDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#BusinessCombinationsScheduleofPurchasePriceDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/BusinessCombinationsScheduleofPurchasePriceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_3ab3cfe1-bdb9-4d7f-9b29-30f74a4ac5c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_3ab3cfe1-bdb9-4d7f-9b29-30f74a4ac5c9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_3ab3cfe1-bdb9-4d7f-9b29-30f74a4ac5c9" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_31193b18-7104-423d-a00d-95c4e675dda6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_cb923aa8-dfde-41bf-b3e5-c0c64d0b5fd7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_31193b18-7104-423d-a00d-95c4e675dda6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_TransactPayBusinessMember_63f22dba-c4bf-4cfe-9b06-303f284b389a" xlink:href="mq-20250930.xsd#mq_TransactPayBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_31193b18-7104-423d-a00d-95c4e675dda6" xlink:to="loc_mq_TransactPayBusinessMember_63f22dba-c4bf-4cfe-9b06-303f284b389a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_91b46d44-b27f-4710-a120-78377ba95e4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_91b46d44-b27f-4710-a120-78377ba95e4c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationContingentConsiderationHoldbackConsideration_d4621cf8-a912-4690-b155-de95ffd3cdb7" xlink:href="mq-20250930.xsd#mq_BusinessCombinationContingentConsiderationHoldbackConsideration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_mq_BusinessCombinationContingentConsiderationHoldbackConsideration_d4621cf8-a912-4690-b155-de95ffd3cdb7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_bea563f3-5552-44fd-a7eb-63ba12f832c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_bea563f3-5552-44fd-a7eb-63ba12f832c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationConsiderationTransferredOther_2cfe41c9-d946-4044-8e49-aa31b8398583" xlink:href="mq-20250930.xsd#mq_BusinessCombinationConsiderationTransferredOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_mq_BusinessCombinationConsiderationTransferredOther_2cfe41c9-d946-4044-8e49-aa31b8398583" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_661494f6-e0f9-462d-98e7-4577b41f36c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_9d4f8cc3-5bf3-4849-bf53-119d8433c061" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_661494f6-e0f9-462d-98e7-4577b41f36c5" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/BusinessCombinationsNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#BusinessCombinationsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/BusinessCombinationsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_4583f935-ed94-4c5d-a258-a2000ec3faf2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_b7e00407-9fea-4cb2-be16-24cf01137d26" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_4583f935-ed94-4c5d-a258-a2000ec3faf2" xlink:to="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_b7e00407-9fea-4cb2-be16-24cf01137d26" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_3c19a543-ab67-4185-b7c9-f3a53096701b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_b7e00407-9fea-4cb2-be16-24cf01137d26" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_3c19a543-ab67-4185-b7c9-f3a53096701b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_3c19a543-ab67-4185-b7c9-f3a53096701b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_3c19a543-ab67-4185-b7c9-f3a53096701b" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_3c19a543-ab67-4185-b7c9-f3a53096701b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e1e543d7-18fe-433e-b7ba-c19a0f7e810c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_3c19a543-ab67-4185-b7c9-f3a53096701b" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e1e543d7-18fe-433e-b7ba-c19a0f7e810c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_TransactPayBusinessMember_949f594a-f933-4a98-987a-09cf176075ec" xlink:href="mq-20250930.xsd#mq_TransactPayBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e1e543d7-18fe-433e-b7ba-c19a0f7e810c" xlink:to="loc_mq_TransactPayBusinessMember_949f594a-f933-4a98-987a-09cf176075ec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_a998c79e-7a20-4a11-9066-4070a968010b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_b7e00407-9fea-4cb2-be16-24cf01137d26" xlink:to="loc_us-gaap_ValuationTechniqueAxis_a998c79e-7a20-4a11-9066-4070a968010b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_a998c79e-7a20-4a11-9066-4070a968010b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_a998c79e-7a20-4a11-9066-4070a968010b" xlink:to="loc_us-gaap_ValuationTechniqueDomain_a998c79e-7a20-4a11-9066-4070a968010b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_2520f95e-b524-4324-990d-657eb64f70d9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_a998c79e-7a20-4a11-9066-4070a968010b" xlink:to="loc_us-gaap_ValuationTechniqueDomain_2520f95e-b524-4324-990d-657eb64f70d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_IndemnificationPurposesMember_858049fe-a5ff-47d8-a746-ce5a78272c13" xlink:href="mq-20250930.xsd#mq_IndemnificationPurposesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_2520f95e-b524-4324-990d-657eb64f70d9" xlink:to="loc_mq_IndemnificationPurposesMember_858049fe-a5ff-47d8-a746-ce5a78272c13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_PostClosingAdjustmentsMember_fd64133c-7675-46ec-9e60-497161d7b664" xlink:href="mq-20250930.xsd#mq_PostClosingAdjustmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_2520f95e-b524-4324-990d-657eb64f70d9" xlink:to="loc_mq_PostClosingAdjustmentsMember_fd64133c-7675-46ec-9e60-497161d7b664" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContingentConsiderationByTypeAxis_a95952da-0edb-472a-bfa3-1f86ae377c23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContingentConsiderationByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_b7e00407-9fea-4cb2-be16-24cf01137d26" xlink:to="loc_us-gaap_ContingentConsiderationByTypeAxis_a95952da-0edb-472a-bfa3-1f86ae377c23" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContingentConsiderationTypeDomain_a95952da-0edb-472a-bfa3-1f86ae377c23_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContingentConsiderationTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContingentConsiderationByTypeAxis_a95952da-0edb-472a-bfa3-1f86ae377c23" xlink:to="loc_us-gaap_ContingentConsiderationTypeDomain_a95952da-0edb-472a-bfa3-1f86ae377c23_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContingentConsiderationTypeDomain_98410853-5b76-40cc-9744-b24ab74399ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContingentConsiderationTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContingentConsiderationByTypeAxis_a95952da-0edb-472a-bfa3-1f86ae377c23" xlink:to="loc_us-gaap_ContingentConsiderationTypeDomain_98410853-5b76-40cc-9744-b24ab74399ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RegulatoryImprovementEarnOutMember_1a344a58-952f-406e-9043-ed719d284e2f" xlink:href="mq-20250930.xsd#mq_RegulatoryImprovementEarnOutMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContingentConsiderationTypeDomain_98410853-5b76-40cc-9744-b24ab74399ed" xlink:to="loc_mq_RegulatoryImprovementEarnOutMember_1a344a58-952f-406e-9043-ed719d284e2f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_DigitalProductsEarnOutMember_c0f31919-e478-4bef-bed5-b2a7b23960b2" xlink:href="mq-20250930.xsd#mq_DigitalProductsEarnOutMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContingentConsiderationTypeDomain_98410853-5b76-40cc-9744-b24ab74399ed" xlink:to="loc_mq_DigitalProductsEarnOutMember_c0f31919-e478-4bef-bed5-b2a7b23960b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_27d4fcf9-61f0-45a2-8319-03584ed46aee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_4583f935-ed94-4c5d-a258-a2000ec3faf2" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_27d4fcf9-61f0-45a2-8319-03584ed46aee" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_65032376-dffe-485b-a29a-3525441f47c8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_4583f935-ed94-4c5d-a258-a2000ec3faf2" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_65032376-dffe-485b-a29a-3525441f47c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationContingentConsiderationHoldbackConsideration_5ad4b77b-6171-445e-8982-f140a5f9e905" xlink:href="mq-20250930.xsd#mq_BusinessCombinationContingentConsiderationHoldbackConsideration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_4583f935-ed94-4c5d-a258-a2000ec3faf2" xlink:to="loc_mq_BusinessCombinationContingentConsiderationHoldbackConsideration_5ad4b77b-6171-445e-8982-f140a5f9e905" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/BusinessCombinationsScheduleofAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#BusinessCombinationsScheduleofAssetsAcquiredandLiabilitiesAssumedDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/BusinessCombinationsScheduleofAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_20d2972f-6346-4802-bd0e-997a24621042" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_20d2972f-6346-4802-bd0e-997a24621042" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_f48a4cdf-0a2d-431e-84e2-dbcd406b355e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_20d2972f-6346-4802-bd0e-997a24621042" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_f48a4cdf-0a2d-431e-84e2-dbcd406b355e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f48a4cdf-0a2d-431e-84e2-dbcd406b355e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f48a4cdf-0a2d-431e-84e2-dbcd406b355e" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f48a4cdf-0a2d-431e-84e2-dbcd406b355e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a591f84-de09-4f67-b47d-490fd0dc14a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f48a4cdf-0a2d-431e-84e2-dbcd406b355e" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a591f84-de09-4f67-b47d-490fd0dc14a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_TransactPayBusinessMember_da020fd8-8f69-4075-988f-28bb28847ef1" xlink:href="mq-20250930.xsd#mq_TransactPayBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a591f84-de09-4f67-b47d-490fd0dc14a9" xlink:to="loc_mq_TransactPayBusinessMember_da020fd8-8f69-4075-988f-28bb28847ef1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b43b8e80-c6bb-4a3a-a476-7717818393fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsTable_20d2972f-6346-4802-bd0e-997a24621042" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b43b8e80-c6bb-4a3a-a476-7717818393fb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_b43b8e80-c6bb-4a3a-a476-7717818393fb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b43b8e80-c6bb-4a3a-a476-7717818393fb" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_b43b8e80-c6bb-4a3a-a476-7717818393fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_fbd059e9-7c21-498c-8285-599459e4ad67" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_b43b8e80-c6bb-4a3a-a476-7717818393fb" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_fbd059e9-7c21-498c-8285-599459e4ad67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_bc637d3a-634c-48e2-99bc-d9d7095969ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_fbd059e9-7c21-498c-8285-599459e4ad67" xlink:to="loc_us-gaap_CustomerRelationshipsMember_bc637d3a-634c-48e2-99bc-d9d7095969ba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_EMILicenseMember_58a0dce9-7a5b-47fc-80a9-c96f5a9bab0f" xlink:href="mq-20250930.xsd#mq_EMILicenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_fbd059e9-7c21-498c-8285-599459e4ad67" xlink:to="loc_mq_EMILicenseMember_58a0dce9-7a5b-47fc-80a9-c96f5a9bab0f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_443cfcd4-1532-42f4-a076-c0b9b26495a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_443cfcd4-1532-42f4-a076-c0b9b26495a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedAssetsAcquiredRestrictedCash_662d3467-33fd-4d66-9421-64e88ec78729" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedAssetsAcquiredRestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedAssetsAcquiredRestrictedCash_662d3467-33fd-4d66-9421-64e88ec78729" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_9d1b4b65-f3db-4a47-953f-0f09fc8bb523" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_9d1b4b65-f3db-4a47-953f-0f09fc8bb523" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_1d25da9d-4bec-4b77-9889-92208473a94d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_1d25da9d-4bec-4b77-9889-92208473a94d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAssetsNet_bfb9e366-ac3e-44c6-b9bf-ed08047adf54" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAssetsNet_bfb9e366-ac3e-44c6-b9bf-ed08047adf54" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_aeea9ed0-d270-4009-a792-b9e9febf3efa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_aeea9ed0-d270-4009-a792-b9e9febf3efa" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_1fd551e1-2cdb-45de-9c95-56a318a6ae7d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_1fd551e1-2cdb-45de-9c95-56a318a6ae7d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedLiabilityAssumedFundsPayableAndAmountsDueToCustomers_f43ed469-39dc-4300-bc77-542a75c6cb14" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedLiabilityAssumedFundsPayableAndAmountsDueToCustomers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedLiabilityAssumedFundsPayableAndAmountsDueToCustomers_f43ed469-39dc-4300-bc77-542a75c6cb14" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_b99d4a5d-6cd7-4fc8-b2ad-4857e9dc0ef8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_b99d4a5d-6cd7-4fc8-b2ad-4857e9dc0ef8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_be3e2941-41ee-41ff-98ed-88af3b9f9120" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_be3e2941-41ee-41ff-98ed-88af3b9f9120" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedLiabilityAssumedAccruedExpensesAndOtherLiabilitiesCurrent_55acbf43-aea8-4b15-89db-8c7c4e696c4a" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedLiabilityAssumedAccruedExpensesAndOtherLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedLiabilityAssumedAccruedExpensesAndOtherLiabilitiesCurrent_55acbf43-aea8-4b15-89db-8c7c4e696c4a" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_e9b4b758-8dc4-42d7-8179-401fa3bf5703" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_e9b4b758-8dc4-42d7-8179-401fa3bf5703" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_73a4883d-0ee5-4468-ac12-617a93c1043f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_73a4883d-0ee5-4468-ac12-617a93c1043f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssetsNet_b81bbaea-21f1-4f7e-bb5e-574cd4e9e806" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssetsNet_b81bbaea-21f1-4f7e-bb5e-574cd4e9e806" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_df9fff94-d286-4b36-8c0f-59807b743218" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_df9fff94-d286-4b36-8c0f-59807b743218" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_aac240f5-2af3-4e04-a3af-52eef81a6c36" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_Goodwill_aac240f5-2af3-4e04-a3af-52eef81a6c36" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill_42077d5d-afef-4102-ac5d-7b82a95e2f76" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_mq_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill_42077d5d-afef-4102-ac5d-7b82a95e2f76" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_ccfdfacf-3158-4e42-adb8-dbcb0ceb99a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsLineItems_1b0b4566-c27b-4992-b49d-ce9157c56e59" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_ccfdfacf-3158-4e42-adb8-dbcb0ceb99a3" xlink:type="arc" order="17"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/GoodwillandIntangibleAssetsnetScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#GoodwillandIntangibleAssetsnetScheduleofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/GoodwillandIntangibleAssetsnetScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_579550a5-5c5b-45a2-bb79-dce741f91cea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_579550a5-5c5b-45a2-bb79-dce741f91cea" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_d5e19567-956c-42e2-8f08-2f9836b7a1a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_579550a5-5c5b-45a2-bb79-dce741f91cea" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_d5e19567-956c-42e2-8f08-2f9836b7a1a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_d5e19567-956c-42e2-8f08-2f9836b7a1a8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_d5e19567-956c-42e2-8f08-2f9836b7a1a8" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_d5e19567-956c-42e2-8f08-2f9836b7a1a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_ae65d1f5-179d-4c11-84c3-b13c5f7ebcf4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_d5e19567-956c-42e2-8f08-2f9836b7a1a8" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_ae65d1f5-179d-4c11-84c3-b13c5f7ebcf4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_0688d98e-8510-47b2-8703-b5e6d24cc39f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_ae65d1f5-179d-4c11-84c3-b13c5f7ebcf4" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_0688d98e-8510-47b2-8703-b5e6d24cc39f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_67b42618-b0ce-47e5-bd36-9ad09133728b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_ae65d1f5-179d-4c11-84c3-b13c5f7ebcf4" xlink:to="loc_us-gaap_CustomerRelationshipsMember_67b42618-b0ce-47e5-bd36-9ad09133728b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_c3c1a749-b0d2-4390-8885-65c718a72233" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_579550a5-5c5b-45a2-bb79-dce741f91cea" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_c3c1a749-b0d2-4390-8885-65c718a72233" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_c3c1a749-b0d2-4390-8885-65c718a72233_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_c3c1a749-b0d2-4390-8885-65c718a72233" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_c3c1a749-b0d2-4390-8885-65c718a72233_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_b424567d-579c-4fc5-b3a7-2d4693424dc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_c3c1a749-b0d2-4390-8885-65c718a72233" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_b424567d-579c-4fc5-b3a7-2d4693424dc2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_EMILicenseMember_83f8a48f-d9c3-407d-a667-ba5bc9a92b9c" xlink:href="mq-20250930.xsd#mq_EMILicenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_b424567d-579c-4fc5-b3a7-2d4693424dc2" xlink:to="loc_mq_EMILicenseMember_83f8a48f-d9c3-407d-a667-ba5bc9a92b9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_ee336568-6a6f-427f-b29b-098b2f62d4d1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_ee336568-6a6f-427f-b29b-098b2f62d4d1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_cebf2a28-ab30-4873-a144-26b2e068f52a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_cebf2a28-ab30-4873-a144-26b2e068f52a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_b3cbb093-ad1e-4fb6-a849-0bddcd5e0c96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_b3cbb093-ad1e-4fb6-a849-0bddcd5e0c96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_a20cd043-b583-4246-acc9-b9d07cfad136" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_a20cd043-b583-4246-acc9-b9d07cfad136" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_f7892c0e-34f2-4ad0-8bed-0660b4a370e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_2bf141e8-823c-47c4-9954-5bda702beaa9" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_f7892c0e-34f2-4ad0-8bed-0660b4a370e0" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/GoodwillandIntangibleAssetsnetNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#GoodwillandIntangibleAssetsnetNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/GoodwillandIntangibleAssetsnetNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_6242665b-9b76-47d7-b115-4af19d0f7b9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_adf6c734-5bea-4ff3-9ca0-bc3e177fef68" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_6242665b-9b76-47d7-b115-4af19d0f7b9f" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_adf6c734-5bea-4ff3-9ca0-bc3e177fef68" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_61d2b2e2-1c03-494c-a56d-8841d19aff2f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_adf6c734-5bea-4ff3-9ca0-bc3e177fef68" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_61d2b2e2-1c03-494c-a56d-8841d19aff2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_61d2b2e2-1c03-494c-a56d-8841d19aff2f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_61d2b2e2-1c03-494c-a56d-8841d19aff2f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_61d2b2e2-1c03-494c-a56d-8841d19aff2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a6e392c4-34bc-4de7-87cf-1c38142e0514" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_61d2b2e2-1c03-494c-a56d-8841d19aff2f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a6e392c4-34bc-4de7-87cf-1c38142e0514" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_4c13f1ec-dc51-4016-b72d-bac4be7cce8b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a6e392c4-34bc-4de7-87cf-1c38142e0514" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_4c13f1ec-dc51-4016-b72d-bac4be7cce8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_3adbcb85-49a1-44a9-ae86-0278515e462a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_a6e392c4-34bc-4de7-87cf-1c38142e0514" xlink:to="loc_us-gaap_CustomerRelationshipsMember_3adbcb85-49a1-44a9-ae86-0278515e462a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_16d6b137-08e4-49f3-9d80-84652045fe07" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_6242665b-9b76-47d7-b115-4af19d0f7b9f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_16d6b137-08e4-49f3-9d80-84652045fe07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_9b254737-ed35-4e30-8208-38ef362ab2fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_6242665b-9b76-47d7-b115-4af19d0f7b9f" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_9b254737-ed35-4e30-8208-38ef362ab2fb" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/ShorttermInvestmentsScheduleofUnrealizedGainLossonShortTermInvestmentsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#ShorttermInvestmentsScheduleofUnrealizedGainLossonShortTermInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/ShorttermInvestmentsScheduleofUnrealizedGainLossonShortTermInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4ec12011-c4e4-4ce4-bfab-460476774172" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4ec12011-c4e4-4ce4-bfab-460476774172" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_0f718441-c503-4833-b2e6-db3d6b5b7421" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4ec12011-c4e4-4ce4-bfab-460476774172" xlink:to="loc_us-gaap_FinancialInstrumentAxis_0f718441-c503-4833-b2e6-db3d6b5b7421" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0f718441-c503-4833-b2e6-db3d6b5b7421_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_0f718441-c503-4833-b2e6-db3d6b5b7421" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0f718441-c503-4833-b2e6-db3d6b5b7421_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d9b255b3-3f47-465d-a72b-9b392e493456" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_0f718441-c503-4833-b2e6-db3d6b5b7421" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d9b255b3-3f47-465d-a72b-9b392e493456" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_9c75c05f-46fb-4dcc-bbdb-11c411f43bc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d9b255b3-3f47-465d-a72b-9b392e493456" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_9c75c05f-46fb-4dcc-bbdb-11c411f43bc2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_f34b43d6-c9d8-4ae4-93f5-1bfccb028cac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d9b255b3-3f47-465d-a72b-9b392e493456" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_f34b43d6-c9d8-4ae4-93f5-1bfccb028cac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CertificatesOfDepositMember_d37ccf4a-695b-409f-a9cf-7c3d5cf01f01" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CertificatesOfDepositMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d9b255b3-3f47-465d-a72b-9b392e493456" xlink:to="loc_us-gaap_CertificatesOfDepositMember_d37ccf4a-695b-409f-a9cf-7c3d5cf01f01" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_9cc8cf20-9d08-44be-8163-48257be8238d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_9cc8cf20-9d08-44be-8163-48257be8238d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_905ec6bc-b4bf-4aba-b5c7-8783cf886a47" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_905ec6bc-b4bf-4aba-b5c7-8783cf886a47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_c551ef9e-0c15-41f5-bf42-370a4c68b4bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_c551ef9e-0c15-41f5-bf42-370a4c68b4bb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent_0cd0c2ba-4012-4475-9099-dd7e19a12611" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_1ce86bf4-c343-48d4-892a-f21839aeea84" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent_0cd0c2ba-4012-4475-9099-dd7e19a12611" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/FairValueMeasurementsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#FairValueMeasurementsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_af636527-7807-4a7d-92d5-862dcb240ddb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_10460c67-1f69-4152-9077-d535c4343bff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_af636527-7807-4a7d-92d5-862dcb240ddb" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_10460c67-1f69-4152-9077-d535c4343bff" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_10460c67-1f69-4152-9077-d535c4343bff" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_a2e309fd-be2a-41eb-a63f-a3b6290c7fe2" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_67e38a6d-afdb-4560-af81-f2b9b854f280" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_MoneyMarketFundsMember_67e38a6d-afdb-4560-af81-f2b9b854f280" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryBillSecuritiesMember_1ca78100-1078-45ae-994b-9b2ebd32e00c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USTreasuryBillSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_USTreasuryBillSecuritiesMember_1ca78100-1078-45ae-994b-9b2ebd32e00c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_14c33090-da3c-4d93-91f8-1f9e79b89982" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_CommercialPaperMember_14c33090-da3c-4d93-91f8-1f9e79b89982" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_06886f2c-ecdd-4daf-b939-11270e46340e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_06886f2c-ecdd-4daf-b939-11270e46340e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CertificatesOfDepositMember_def11662-46fd-4688-aeb0-b0a0a0723ea2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CertificatesOfDepositMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_CertificatesOfDepositMember_def11662-46fd-4688-aeb0-b0a0a0723ea2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_93c798f1-16b6-4335-a48d-9b2467808a62" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_93c798f1-16b6-4335-a48d-9b2467808a62" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_e73c14a6-fd59-402e-ba02-b388c38c82a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_659fe789-a5a6-4f48-b20a-69669eeefa32" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_e73c14a6-fd59-402e-ba02-b388c38c82a8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_10460c67-1f69-4152-9077-d535c4343bff" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8e21d78f-4716-473a-b98f-3361cec0f92d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_0e55cc4d-d1f0-4fb1-a98c-50132f732ae6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8e21d78f-4716-473a-b98f-3361cec0f92d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_71fdd5d4-37c9-4520-9da6-c2a0e593d61c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8e21d78f-4716-473a-b98f-3361cec0f92d" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_71fdd5d4-37c9-4520-9da6-c2a0e593d61c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_7cd898ad-6ba8-4cf9-8975-f538e0cb3e0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8e21d78f-4716-473a-b98f-3361cec0f92d" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_7cd898ad-6ba8-4cf9-8975-f538e0cb3e0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_da6fd56f-edc9-4a86-94e9-775831472939" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8e21d78f-4716-473a-b98f-3361cec0f92d" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_da6fd56f-edc9-4a86-94e9-775831472939" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_fb4691bc-3925-4c14-ba22-70588c943123" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_10460c67-1f69-4152-9077-d535c4343bff" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_fb4691bc-3925-4c14-ba22-70588c943123" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_fb4691bc-3925-4c14-ba22-70588c943123_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_fb4691bc-3925-4c14-ba22-70588c943123" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_fb4691bc-3925-4c14-ba22-70588c943123_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_972e2904-6dd2-4556-a9d2-f24775e57620" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_fb4691bc-3925-4c14-ba22-70588c943123" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_972e2904-6dd2-4556-a9d2-f24775e57620" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_48405848-08d5-4947-8e83-0babc4bc9d11" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_972e2904-6dd2-4556-a9d2-f24775e57620" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_48405848-08d5-4947-8e83-0babc4bc9d11" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_af636527-7807-4a7d-92d5-862dcb240ddb" xlink:to="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsAtCarryingValue_725ddb31-e1b4-47e9-a4ab-672f8415e34c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:to="loc_us-gaap_CashEquivalentsAtCarryingValue_725ddb31-e1b4-47e9-a4ab-672f8415e34c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_86655034-50cb-4677-afe3-7d9f2c95c145" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_86655034-50cb-4677-afe3-7d9f2c95c145" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_e52eee39-fefb-41df-94f1-2721058c8a3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:to="loc_us-gaap_RestrictedCash_e52eee39-fefb-41df-94f1-2721058c8a3c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_a15df6ab-f6b9-46d1-964a-52435b857f95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_1633d03b-73e0-436d-bb18-6b1d90a05d32" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_a15df6ab-f6b9-46d1-964a-52435b857f95" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrentAbstract_7ca9d32c-d35b-4509-b650-f16a536c0091" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_af636527-7807-4a7d-92d5-862dcb240ddb" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrentAbstract_7ca9d32c-d35b-4509-b650-f16a536c0091" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_50a07232-ac08-445e-900c-72d073db6f3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrentAbstract_7ca9d32c-d35b-4509-b650-f16a536c0091" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_50a07232-ac08-445e-900c-72d073db6f3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_28f3f6ce-91bf-4d0b-ab01-b68db5a79cd9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrentAbstract_7ca9d32c-d35b-4509-b650-f16a536c0091" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_28f3f6ce-91bf-4d0b-ab01-b68db5a79cd9" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/CertainBalanceSheetComponentsScheduleofPropertyandEquipmentDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#CertainBalanceSheetComponentsScheduleofPropertyandEquipmentDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CertainBalanceSheetComponentsScheduleofPropertyandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_8a83ab39-746f-48f8-b1b2-073fcc2fd714" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_51b6bbe8-57d0-466e-8797-c463fe0d8424" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_8a83ab39-746f-48f8-b1b2-073fcc2fd714" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_51b6bbe8-57d0-466e-8797-c463fe0d8424" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1d43e101-aefb-4af8-9b3e-2db4680e6718" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_51b6bbe8-57d0-466e-8797-c463fe0d8424" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1d43e101-aefb-4af8-9b3e-2db4680e6718" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1d43e101-aefb-4af8-9b3e-2db4680e6718_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1d43e101-aefb-4af8-9b3e-2db4680e6718" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1d43e101-aefb-4af8-9b3e-2db4680e6718_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1d43e101-aefb-4af8-9b3e-2db4680e6718" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_e059ddb8-b967-4584-8214-87063367d9f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_e059ddb8-b967-4584-8214-87063367d9f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_c751a68e-8e2f-47ed-a612-96af7647b3a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:to="loc_us-gaap_ComputerEquipmentMember_c751a68e-8e2f-47ed-a612-96af7647b3a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_f4da480d-6a64-4dbf-a42e-82e8a8a6d9e4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_f4da480d-6a64-4dbf-a42e-82e8a8a6d9e4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_681cfac7-07a1-4a33-b996-54e856e3b897" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_233e05fd-7df8-4973-9548-20c55667020b" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_681cfac7-07a1-4a33-b996-54e856e3b897" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_e48bbd07-6356-4b97-88b5-995a92c17ab9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_8a83ab39-746f-48f8-b1b2-073fcc2fd714" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_e48bbd07-6356-4b97-88b5-995a92c17ab9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2000d408-c19d-45c4-8a29-b3f6db9f6349" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_8a83ab39-746f-48f8-b1b2-073fcc2fd714" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2000d408-c19d-45c4-8a29-b3f6db9f6349" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_b3e36076-8abe-43cb-aa98-4ef63a21c775" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_8a83ab39-746f-48f8-b1b2-073fcc2fd714" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_b3e36076-8abe-43cb-aa98-4ef63a21c775" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/CertainBalanceSheetComponentsNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#CertainBalanceSheetComponentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CertainBalanceSheetComponentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_49467116-ce2b-4151-85bd-42a4e1decf7a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3a31bcc5-3c65-45fb-bb15-2febf5b90854" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_49467116-ce2b-4151-85bd-42a4e1decf7a" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3a31bcc5-3c65-45fb-bb15-2febf5b90854" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_36d26c5b-1eaa-4a71-b326-24845e776e5f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3a31bcc5-3c65-45fb-bb15-2febf5b90854" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_36d26c5b-1eaa-4a71-b326-24845e776e5f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_36d26c5b-1eaa-4a71-b326-24845e776e5f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_36d26c5b-1eaa-4a71-b326-24845e776e5f" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_36d26c5b-1eaa-4a71-b326-24845e776e5f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_9a14b818-6598-4081-9d30-e6a9cbddb21c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_36d26c5b-1eaa-4a71-b326-24845e776e5f" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_9a14b818-6598-4081-9d30-e6a9cbddb21c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentMember_8261299f-bc83-46d1-af0a-4ed15abcc884" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_9a14b818-6598-4081-9d30-e6a9cbddb21c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentMember_8261299f-bc83-46d1-af0a-4ed15abcc884" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_79ebe8cb-b39e-4670-b476-dd4bea4150e4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_49467116-ce2b-4151-85bd-42a4e1decf7a" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_79ebe8cb-b39e-4670-b476-dd4bea4150e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareAdditions_39cd2fdb-3780-49d9-80b4-86c8d1124933" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareAdditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_49467116-ce2b-4151-85bd-42a4e1decf7a" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareAdditions_39cd2fdb-3780-49d9-80b4-86c8d1124933" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/LeasesNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#LeasesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/LeasesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionTable_ff4bc5b4-6cb6-439a-8bba-694f7fc6d4a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_LesseeLeaseDescriptionTable_ff4bc5b4-6cb6-439a-8bba-694f7fc6d4a7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_ff4bc5b4-6cb6-439a-8bba-694f7fc6d4a7" xlink:to="loc_srt_CounterpartyNameAxis_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_365c4306-7771-4b9f-9d7b-04fb7abf078c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_f1c244b9-dcbe-49f5-9525-7c0e5b9e8d47" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_365c4306-7771-4b9f-9d7b-04fb7abf078c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_OaklandLeaseMember_682c8706-28a0-47fc-b86c-ce77d4901a90" xlink:href="mq-20250930.xsd#mq_OaklandLeaseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_365c4306-7771-4b9f-9d7b-04fb7abf078c" xlink:to="loc_mq_OaklandLeaseMember_682c8706-28a0-47fc-b86c-ce77d4901a90" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_5ab7c911-4dda-41fc-b470-afa6e01af3b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_ff4bc5b4-6cb6-439a-8bba-694f7fc6d4a7" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_5ab7c911-4dda-41fc-b470-afa6e01af3b9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_5ab7c911-4dda-41fc-b470-afa6e01af3b9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_5ab7c911-4dda-41fc-b470-afa6e01af3b9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_5ab7c911-4dda-41fc-b470-afa6e01af3b9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a155110-7712-470d-8319-f1fcf44f0ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_5ab7c911-4dda-41fc-b470-afa6e01af3b9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a155110-7712-470d-8319-f1fcf44f0ad7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_TransactPayBusinessMember_8a05aca4-f5c2-4fc2-a07f-fddd415af050" xlink:href="mq-20250930.xsd#mq_TransactPayBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2a155110-7712-470d-8319-f1fcf44f0ad7" xlink:to="loc_mq_TransactPayBusinessMember_8a05aca4-f5c2-4fc2-a07f-fddd415af050" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_OperatingLeaseNumberOfSquareFeet_c0513e89-df8e-489b-aca0-a727893321bd" xlink:href="mq-20250930.xsd#mq_OperatingLeaseNumberOfSquareFeet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_mq_OperatingLeaseNumberOfSquareFeet_c0513e89-df8e-489b-aca0-a727893321bd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_900208ed-a092-4f44-bafd-52d4288cc299" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_900208ed-a092-4f44-bafd-52d4288cc299" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_9f404a51-8572-4b8a-b443-1ebb9367b10e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_9f404a51-8572-4b8a-b443-1ebb9367b10e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_BusinessCombinationRecognizedLiabilityAssumedLeaseObligationNumberOfLease_88af8ed1-db6c-4a01-ba1c-172d2571ef3e" xlink:href="mq-20250930.xsd#mq_BusinessCombinationRecognizedLiabilityAssumedLeaseObligationNumberOfLease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_mq_BusinessCombinationRecognizedLiabilityAssumedLeaseObligationNumberOfLease_88af8ed1-db6c-4a01-ba1c-172d2571ef3e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_60d172b7-9d0e-4a52-b26b-67d5a69d84c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_60d172b7-9d0e-4a52-b26b-67d5a69d84c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_c193fe6c-4b7e-4d47-8b8d-e51dbb500376" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_OperatingLeaseLiability_c193fe6c-4b7e-4d47-8b8d-e51dbb500376" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_LesseeOperatingLeasesNotYetCommencedCommitments_e6f6b11c-7d47-4f67-9702-cf8501213340" xlink:href="mq-20250930.xsd#mq_LesseeOperatingLeasesNotYetCommencedCommitments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_mq_LesseeOperatingLeasesNotYetCommencedCommitments_e6f6b11c-7d47-4f67-9702-cf8501213340" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseTermOfContract_def7dc2a-57a0-4a43-a73d-62ead19b293c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_c4a90618-a3a5-4acf-a5e1-f4a84ba964f4" xlink:to="loc_us-gaap_LesseeOperatingLeaseTermOfContract_def7dc2a-57a0-4a43-a73d-62ead19b293c" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/CommitmentsandContingenciesDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#CommitmentsandContingenciesDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/CommitmentsandContingenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_8e90ef35-29c9-47fd-97c8-16c61f737887" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_us-gaap_CreditFacilityAxis_8e90ef35-29c9-47fd-97c8-16c61f737887" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_8e90ef35-29c9-47fd-97c8-16c61f737887_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_8e90ef35-29c9-47fd-97c8-16c61f737887" xlink:to="loc_us-gaap_CreditFacilityDomain_8e90ef35-29c9-47fd-97c8-16c61f737887_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_aa6af90d-6b2a-45e7-8dec-5bdb46417d4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_8e90ef35-29c9-47fd-97c8-16c61f737887" xlink:to="loc_us-gaap_CreditFacilityDomain_aa6af90d-6b2a-45e7-8dec-5bdb46417d4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialStandbyLetterOfCreditMember_7ef23175-bacd-4a95-b78d-250f0e0c816f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialStandbyLetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_aa6af90d-6b2a-45e7-8dec-5bdb46417d4f" xlink:to="loc_us-gaap_FinancialStandbyLetterOfCreditMember_7ef23175-bacd-4a95-b78d-250f0e0c816f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_CardAndEMoneyWalletProgramsMember_4a76d3bb-cb2f-473e-8914-177569af3592" xlink:href="mq-20250930.xsd#mq_CardAndEMoneyWalletProgramsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_aa6af90d-6b2a-45e7-8dec-5bdb46417d4f" xlink:to="loc_mq_CardAndEMoneyWalletProgramsMember_4a76d3bb-cb2f-473e-8914-177569af3592" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_e4b8d940-5bbe-4863-a77b-8d39b996c224" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_e4b8d940-5bbe-4863-a77b-8d39b996c224" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_e4b8d940-5bbe-4863-a77b-8d39b996c224_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_e4b8d940-5bbe-4863-a77b-8d39b996c224" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_e4b8d940-5bbe-4863-a77b-8d39b996c224_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_7460fc62-04a5-4cf0-88e2-e5c056076fb9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_e4b8d940-5bbe-4863-a77b-8d39b996c224" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_7460fc62-04a5-4cf0-88e2-e5c056076fb9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RestrictedCashAndCashEquivalentsCurrentMember_5561946a-a541-4b42-8c8b-b7542f63cb1e" xlink:href="mq-20250930.xsd#mq_RestrictedCashAndCashEquivalentsCurrentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_7460fc62-04a5-4cf0-88e2-e5c056076fb9" xlink:to="loc_mq_RestrictedCashAndCashEquivalentsCurrentMember_5561946a-a541-4b42-8c8b-b7542f63cb1e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_srt_StatementScenarioAxis_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8" xlink:to="loc_srt_ScenarioUnspecifiedDomain_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_f96534d9-5be4-4cf5-a67c-54f078bd0606" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_ebdfa3d2-b2f7-4f5a-935c-283d796ceea8" xlink:to="loc_srt_ScenarioUnspecifiedDomain_f96534d9-5be4-4cf5-a67c-54f078bd0606" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_dacedd21-6cf2-45ea-a890-7d954ed061d8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_f96534d9-5be4-4cf5-a67c-54f078bd0606" xlink:to="loc_srt_ScenarioForecastMember_dacedd21-6cf2-45ea-a890-7d954ed061d8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_6d7590ba-f321-46a0-a288-b71561ff0d0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_6d7590ba-f321-46a0-a288-b71561ff0d0d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_6d7590ba-f321-46a0-a288-b71561ff0d0d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_6d7590ba-f321-46a0-a288-b71561ff0d0d" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_6d7590ba-f321-46a0-a288-b71561ff0d0d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_5f6d61cc-87ea-40e5-aa2c-e5ff394e138c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_6d7590ba-f321-46a0-a288-b71561ff0d0d" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_5f6d61cc-87ea-40e5-aa2c-e5ff394e138c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_3598726b-5479-48a8-8276-7ab147131a5d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_5f6d61cc-87ea-40e5-aa2c-e5ff394e138c" xlink:to="loc_us-gaap_MoneyMarketFundsMember_3598726b-5479-48a8-8276-7ab147131a5d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseAxis_4cb8ddf1-1260-44ef-8598-4c152d2296de" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_srt_LitigationCaseAxis_4cb8ddf1-1260-44ef-8598-4c152d2296de" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_4cb8ddf1-1260-44ef-8598-4c152d2296de_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_4cb8ddf1-1260-44ef-8598-4c152d2296de" xlink:to="loc_srt_LitigationCaseTypeDomain_4cb8ddf1-1260-44ef-8598-4c152d2296de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_7393ce29-dc16-424a-9b9c-3bfee7b38012" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_4cb8ddf1-1260-44ef-8598-4c152d2296de" xlink:to="loc_srt_LitigationCaseTypeDomain_7393ce29-dc16-424a-9b9c-3bfee7b38012" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_SecuritiesActionsMember_3a5cd600-6c0b-4512-bdc6-8d3dcc5a8a09" xlink:href="mq-20250930.xsd#mq_SecuritiesActionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_7393ce29-dc16-424a-9b9c-3bfee7b38012" xlink:to="loc_mq_SecuritiesActionsMember_3a5cd600-6c0b-4512-bdc6-8d3dcc5a8a09" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusAxis_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_us-gaap_LitigationStatusAxis_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LitigationStatusAxis_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd" xlink:to="loc_us-gaap_LitigationStatusDomain_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_9d97ba1c-c98c-4ba8-8353-0d832aa94a15" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LitigationStatusAxis_d5f3e2cc-f1ca-4577-abaa-87f5f98912bd" xlink:to="loc_us-gaap_LitigationStatusDomain_9d97ba1c-c98c-4ba8-8353-0d832aa94a15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SettledLitigationMember_36f8dca3-aabe-4ef9-8224-6b01b50258a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SettledLitigationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationStatusDomain_9d97ba1c-c98c-4ba8-8353-0d832aa94a15" xlink:to="loc_us-gaap_SettledLitigationMember_36f8dca3-aabe-4ef9-8224-6b01b50258a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_1945337c-83e3-49a8-980d-ace69de1577f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_0635374c-63c5-419a-94ba-4e079026648f" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_1945337c-83e3-49a8-980d-ace69de1577f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_1945337c-83e3-49a8-980d-ace69de1577f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_1945337c-83e3-49a8-980d-ace69de1577f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_1945337c-83e3-49a8-980d-ace69de1577f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_d6e9371f-28c2-446b-9cc2-4d0b6d02e0f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_1945337c-83e3-49a8-980d-ace69de1577f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_d6e9371f-28c2-446b-9cc2-4d0b6d02e0f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_94c8e08a-758e-446a-9672-2526c6f851f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_d6e9371f-28c2-446b-9cc2-4d0b6d02e0f1" xlink:to="loc_us-gaap_SubsequentEventMember_94c8e08a-758e-446a-9672-2526c6f851f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_4292935b-895d-4667-9f2a-0d762b363e96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_4292935b-895d-4667-9f2a-0d762b363e96" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositAssets_afae2770-b64e-424b-8aef-a0d3ecafb60c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepositAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_DepositAssets_afae2770-b64e-424b-8aef-a0d3ecafb60c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_bf974225-9d49-4a75-affc-61f15dad13c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_bf974225-9d49-4a75-affc-61f15dad13c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_b40a6ac1-0308-47d8-95dd-84cc33ef22a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_b40a6ac1-0308-47d8-95dd-84cc33ef22a7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRestrictedAssetsCurrent_90e70843-4848-4b72-944c-415d7a507efb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherRestrictedAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_OtherRestrictedAssetsCurrent_90e70843-4848-4b72-944c-415d7a507efb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashCurrent_2c04b8c4-b17b-4dd1-95de-67a7b4f1a33b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_RestrictedCashCurrent_2c04b8c4-b17b-4dd1-95de-67a7b4f1a33b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_dde4d760-a51f-4257-8751-1ecfa1aecbc6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_RestrictedCash_dde4d760-a51f-4257-8751-1ecfa1aecbc6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForLegalSettlements_ef74bc35-f1d8-4fa5-9056-800ba79319ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForLegalSettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_PaymentsForLegalSettlements_ef74bc35-f1d8-4fa5-9056-800ba79319ed" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LegalFees_b35f50d2-9e36-4230-b3e6-2352de395772" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LegalFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_us-gaap_LegalFees_b35f50d2-9e36-4230-b3e6-2352de395772" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductibleAmount_f0be9fbe-ca03-4389-9450-ae5d4f4d3fee" xlink:href="mq-20250930.xsd#mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductibleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductibleAmount_f0be9fbe-ca03-4389-9450-ae5d4f4d3fee" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductiblePayment_5828a53d-d051-424c-8885-9df2d909fe22" xlink:href="mq-20250930.xsd#mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductiblePayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_93fd71f6-db4d-4787-b086-2a0b7483ef4a" xlink:to="loc_mq_LossContingencyDirectorsAndOfficersInsurancePolicyDeductiblePayment_5828a53d-d051-424c-8885-9df2d909fe22" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/StockIncentivePlansScheduleofShareBasedCompensationExpenseDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#StockIncentivePlansScheduleofShareBasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/StockIncentivePlansScheduleofShareBasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_c1cca4ce-0f73-4c2e-be1f-f029adb556c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_c1cca4ce-0f73-4c2e-be1f-f029adb556c2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_600d57d3-bcb0-4cd1-afc4-930d5d2a7025" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_c1cca4ce-0f73-4c2e-be1f-f029adb556c2" xlink:to="loc_us-gaap_AwardTypeAxis_600d57d3-bcb0-4cd1-afc4-930d5d2a7025" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_600d57d3-bcb0-4cd1-afc4-930d5d2a7025_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_600d57d3-bcb0-4cd1-afc4-930d5d2a7025" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_600d57d3-bcb0-4cd1-afc4-930d5d2a7025_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_600d57d3-bcb0-4cd1-afc4-930d5d2a7025" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_0aaa8043-43c7-4f24-8953-24badfe7b96f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_0aaa8043-43c7-4f24-8953-24badfe7b96f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember_8fdb7730-3b53-4fe9-9253-d3e286f38bd4" xlink:href="mq-20250930.xsd#mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:to="loc_mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember_8fdb7730-3b53-4fe9-9253-d3e286f38bd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_41492186-9423-4331-a871-211a0f844040" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:to="loc_us-gaap_PerformanceSharesMember_41492186-9423-4331-a871-211a0f844040" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_177ef6cb-71a0-49a1-871b-c143198e7cde" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fc994191-30d3-4c25-af1d-877d14327bd8" xlink:to="loc_us-gaap_EmployeeStockMember_177ef6cb-71a0-49a1-871b-c143198e7cde" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_1a98f805-3787-432e-bec4-215351e4a61d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_1a98f805-3787-432e-bec4-215351e4a61d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_ShareBasedCompensationRecordedWithinCompensationAndBenefits_42e29488-7146-4faf-9f5c-c71b8a60c3d6" xlink:href="mq-20250930.xsd#mq_ShareBasedCompensationRecordedWithinCompensationAndBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:to="loc_mq_ShareBasedCompensationRecordedWithinCompensationAndBenefits_42e29488-7146-4faf-9f5c-c71b8a60c3d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_ffdec5cc-1634-40db-bace-dc9402ef9765" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_ffdec5cc-1634-40db-bace-dc9402ef9765" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_cf8aebf5-7bdc-4d05-a29d-06705af4de96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_c4c383e4-3908-4df5-94a6-b8c7cf26dc66" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_cf8aebf5-7bdc-4d05-a29d-06705af4de96" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/StockIncentivePlansScheduleofRestrictedStockUnitsandPerformanceStockUnitsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#StockIncentivePlansScheduleofRestrictedStockUnitsandPerformanceStockUnitsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/StockIncentivePlansScheduleofRestrictedStockUnitsandPerformanceStockUnitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_dbb278ed-2720-45ce-9fcd-916f8ae8ff21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_74e097ae-a20b-476c-8d56-969680b7c173" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_dbb278ed-2720-45ce-9fcd-916f8ae8ff21" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_74e097ae-a20b-476c-8d56-969680b7c173" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_66254c2d-51c1-48b4-bcf2-569ecac11e03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_74e097ae-a20b-476c-8d56-969680b7c173" xlink:to="loc_us-gaap_AwardTypeAxis_66254c2d-51c1-48b4-bcf2-569ecac11e03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_66254c2d-51c1-48b4-bcf2-569ecac11e03_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_66254c2d-51c1-48b4-bcf2-569ecac11e03" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_66254c2d-51c1-48b4-bcf2-569ecac11e03_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_96fc0e1c-04ed-4897-a7b9-08982d8b1073" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_66254c2d-51c1-48b4-bcf2-569ecac11e03" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_96fc0e1c-04ed-4897-a7b9-08982d8b1073" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RestrictedStockUnitsAndPerformanceStockUnitsMember_ada9ca29-c2c8-4f8e-8359-36f2a9b2f1fa" xlink:href="mq-20250930.xsd#mq_RestrictedStockUnitsAndPerformanceStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_96fc0e1c-04ed-4897-a7b9-08982d8b1073" xlink:to="loc_mq_RestrictedStockUnitsAndPerformanceStockUnitsMember_ada9ca29-c2c8-4f8e-8359-36f2a9b2f1fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_dbb278ed-2720-45ce-9fcd-916f8ae8ff21" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_f733fe93-2265-4f29-8ab6-7420a4c8914f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_f733fe93-2265-4f29-8ab6-7420a4c8914f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_abdc9ef2-5290-48a8-ae24-6721097c56d0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_abdc9ef2-5290-48a8-ae24-6721097c56d0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_3f47c2c1-eed7-4c84-b891-1eb55cdada23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_3f47c2c1-eed7-4c84-b891-1eb55cdada23" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_b1a65a9a-889f-43f8-874b-9eecf6ee0605" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b1d06113-e163-4e07-ac7c-d4a40188fa50" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_b1a65a9a-889f-43f8-874b-9eecf6ee0605" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_791eb56e-bf2a-4263-9f1e-1dabc7c9a7f7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_dbb278ed-2720-45ce-9fcd-916f8ae8ff21" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_07623fb2-7998-4d65-a188-b9cd77267fab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_07623fb2-7998-4d65-a188-b9cd77267fab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_fa3586b7-bca7-41bf-b99e-2815b2696b9e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_fa3586b7-bca7-41bf-b99e-2815b2696b9e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_e1d368e2-ba83-4e2b-8f5b-bc0c2d2f1ef6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_e1d368e2-ba83-4e2b-8f5b-bc0c2d2f1ef6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_b5a0edab-0a1f-48c8-bac8-8f2bfd2813a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_6df0c02c-10e2-4702-b480-ab50184f6d0a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_b5a0edab-0a1f-48c8-bac8-8f2bfd2813a3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_9e94f1b1-f715-4d8a-8054-fbd945eac0e4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/StockIncentivePlansNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#StockIncentivePlansNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/StockIncentivePlansNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_f86d9437-4685-405d-af5b-507591b859a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_3cd9a8b5-0c37-486c-99e2-8b7ce492eb04" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_f86d9437-4685-405d-af5b-507591b859a9" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_3cd9a8b5-0c37-486c-99e2-8b7ce492eb04" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_771252cc-0074-4c17-900d-76c0bc569c08" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_3cd9a8b5-0c37-486c-99e2-8b7ce492eb04" xlink:to="loc_us-gaap_AwardTypeAxis_771252cc-0074-4c17-900d-76c0bc569c08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_771252cc-0074-4c17-900d-76c0bc569c08_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_771252cc-0074-4c17-900d-76c0bc569c08" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_771252cc-0074-4c17-900d-76c0bc569c08_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fafcaab2-e6bf-4cca-9403-9896bee5015c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_771252cc-0074-4c17-900d-76c0bc569c08" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fafcaab2-e6bf-4cca-9403-9896bee5015c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RestrictedStockUnitsAndPerformanceStockUnitsMember_140d2f25-597c-4c24-9fe2-1eb617d9c2ad" xlink:href="mq-20250930.xsd#mq_RestrictedStockUnitsAndPerformanceStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fafcaab2-e6bf-4cca-9403-9896bee5015c" xlink:to="loc_mq_RestrictedStockUnitsAndPerformanceStockUnitsMember_140d2f25-597c-4c24-9fe2-1eb617d9c2ad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember_b5aa30de-3f1b-4df1-ae2c-56698d285fe2" xlink:href="mq-20250930.xsd#mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_fafcaab2-e6bf-4cca-9403-9896bee5015c" xlink:to="loc_mq_EmployeeStockOptionExcludingCEOLongTermPerformanceAwardMember_b5aa30de-3f1b-4df1-ae2c-56698d285fe2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_43f6cb63-10d3-4deb-98f6-00f8d4abd635" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_f86d9437-4685-405d-af5b-507591b859a9" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_43f6cb63-10d3-4deb-98f6-00f8d4abd635" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_b220a7e2-686b-4c82-b802-294b29315121" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_f86d9437-4685-405d-af5b-507591b859a9" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_b220a7e2-686b-4c82-b802-294b29315121" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/StockIncentivePlansScheduleofStockOptionActivityUnderStockIncentivePlanDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#StockIncentivePlansScheduleofStockOptionActivityUnderStockIncentivePlanDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/StockIncentivePlansScheduleofStockOptionActivityUnderStockIncentivePlanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_83d0ad38-1cbb-4f2e-adca-c86780919f98" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e96094e6-dc15-4827-bfa7-424b3e14ac7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_83d0ad38-1cbb-4f2e-adca-c86780919f98" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e96094e6-dc15-4827-bfa7-424b3e14ac7e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_878d3ac2-866f-4127-bc63-6f9153d20461" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e96094e6-dc15-4827-bfa7-424b3e14ac7e" xlink:to="loc_us-gaap_AwardTypeAxis_878d3ac2-866f-4127-bc63-6f9153d20461" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_878d3ac2-866f-4127-bc63-6f9153d20461_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_878d3ac2-866f-4127-bc63-6f9153d20461" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_878d3ac2-866f-4127-bc63-6f9153d20461_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_61e7dd73-f381-4d8d-80f2-e78d000cd41b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_878d3ac2-866f-4127-bc63-6f9153d20461" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_61e7dd73-f381-4d8d-80f2-e78d000cd41b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_0487c002-ff66-4549-a922-5b374e6b4121" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_61e7dd73-f381-4d8d-80f2-e78d000cd41b" xlink:to="loc_us-gaap_EmployeeStockOptionMember_0487c002-ff66-4549-a922-5b374e6b4121" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_83d0ad38-1cbb-4f2e-adca-c86780919f98" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_c9d28232-c9a0-4108-b88f-70bb38cd1cae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_c9d28232-c9a0-4108-b88f-70bb38cd1cae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_ffa95100-87d2-4d88-96c2-b2dd1e46c642" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_ffa95100-87d2-4d88-96c2-b2dd1e46c642" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_9eeb700a-3233-4379-acba-da62e5138f16" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_9eeb700a-3233-4379-acba-da62e5138f16" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_fdf83e1b-0394-45c7-ba8c-a2a0ef67fa93" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_fdf83e1b-0394-45c7-ba8c-a2a0ef67fa93" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_c8f61df4-540a-4351-9276-d7b03647517f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber_160d5c9e-56d2-4620-821c-f17c87c8ece8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber_160d5c9e-56d2-4620-821c-f17c87c8ece8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_1c06b435-b794-4471-8325-766e9ca97df0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_8364f7fa-8d82-47d1-858b-b4bce3073ee9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_1c06b435-b794-4471-8325-766e9ca97df0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_83d0ad38-1cbb-4f2e-adca-c86780919f98" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_72cc8286-5e00-4251-8ed7-98722dd6d379" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_72cc8286-5e00-4251-8ed7-98722dd6d379" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_85390ddd-b4c5-425d-bbb6-b0254bccd00f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_85390ddd-b4c5-425d-bbb6-b0254bccd00f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_67dabb1e-240a-4e9b-aa04-fe3235ce5ea0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_67dabb1e-240a-4e9b-aa04-fe3235ce5ea0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_5fe1bb15-7786-44ac-972b-d9b7d93d663f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_5fe1bb15-7786-44ac-972b-d9b7d93d663f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_8b1eb701-3269-4203-922c-070bf05ed174" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_5028d92d-2b9e-434f-af0f-3982b42a6a09" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_5028d92d-2b9e-434f-af0f-3982b42a6a09" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_599a4ebb-3416-461f-849e-2dcf797ead88" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_9e3affce-23c8-4f13-92fb-c771ba469475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_599a4ebb-3416-461f-849e-2dcf797ead88" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_83d0ad38-1cbb-4f2e-adca-c86780919f98" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_88236395-e8df-4aae-8866-cea34eb90169" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_88236395-e8df-4aae-8866-cea34eb90169" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_a35252ef-c923-498f-9d49-f3f4b6f70cb8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_a35252ef-c923-498f-9d49-f3f4b6f70cb8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_1fc053c6-8d33-4e0b-830f-252283c18618" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_1fc053c6-8d33-4e0b-830f-252283c18618" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_d8d6d7e3-e9ff-424a-8e73-5052a85674e5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_d8d6d7e3-e9ff-424a-8e73-5052a85674e5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_bdb0b989-bdab-4cc6-a61e-1047867c2e20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_bdb0b989-bdab-4cc6-a61e-1047867c2e20" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_29a61f79-614d-4fe3-b850-34da05ad0e8b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_875d9562-a503-4e2c-bc03-c80be46640c2" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_29a61f79-614d-4fe3-b850-34da05ad0e8b" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/StockholdersEquityTransactionsDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#StockholdersEquityTransactionsDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/StockholdersEquityTransactionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightTable_580eea76-8421-4a65-9599-78336564922d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_ClassOfWarrantOrRightTable_580eea76-8421-4a65-9599-78336564922d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_d509d2d2-d290-4c45-82d3-f56397f0ee87" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_580eea76-8421-4a65-9599-78336564922d" xlink:to="loc_srt_ShareRepurchaseProgramAxis_d509d2d2-d290-4c45-82d3-f56397f0ee87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_d509d2d2-d290-4c45-82d3-f56397f0ee87_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_d509d2d2-d290-4c45-82d3-f56397f0ee87" xlink:to="loc_srt_ShareRepurchaseProgramDomain_d509d2d2-d290-4c45-82d3-f56397f0ee87_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_97befd53-7a67-4696-b782-13f255926a71" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_d509d2d2-d290-4c45-82d3-f56397f0ee87" xlink:to="loc_srt_ShareRepurchaseProgramDomain_97befd53-7a67-4696-b782-13f255926a71" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_A2024ShareRepurchaseProgramMember_815976c6-1f7b-4459-82ba-5bf113c94305" xlink:href="mq-20250930.xsd#mq_A2024ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_97befd53-7a67-4696-b782-13f255926a71" xlink:to="loc_mq_A2024ShareRepurchaseProgramMember_815976c6-1f7b-4459-82ba-5bf113c94305" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_A2025ShareRepurchaseProgramMember_b9b20f4b-52cc-4485-8c97-da133533e1e9" xlink:href="mq-20250930.xsd#mq_A2025ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_97befd53-7a67-4696-b782-13f255926a71" xlink:to="loc_mq_A2025ShareRepurchaseProgramMember_b9b20f4b-52cc-4485-8c97-da133533e1e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_A2023ShareRepurchaseProgramMember_310bf45b-809f-4612-bb8a-19467e1cb9f8" xlink:href="mq-20250930.xsd#mq_A2023ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_97befd53-7a67-4696-b782-13f255926a71" xlink:to="loc_mq_A2023ShareRepurchaseProgramMember_310bf45b-809f-4612-bb8a-19467e1cb9f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_3a090abf-232a-4120-9e8c-8242a9e767c9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_3a090abf-232a-4120-9e8c-8242a9e767c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_55821fb9-daf2-4f06-996a-dfe2437a9a77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_55821fb9-daf2-4f06-996a-dfe2437a9a77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_d4a590bc-424a-4537-a4e0-2f7d0e3de05d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_d4a590bc-424a-4537-a4e0-2f7d0e3de05d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_dc9e7dab-25a5-4f32-a2f8-7d7e15b8853f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_dc9e7dab-25a5-4f32-a2f8-7d7e15b8853f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_StockRepurchasedAndRetiredDuringPeriodTransactionCosts_b9d2d8b1-15ad-4d4d-bb84-6d23e6edb11c" xlink:href="mq-20250930.xsd#mq_StockRepurchasedAndRetiredDuringPeriodTransactionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_mq_StockRepurchasedAndRetiredDuringPeriodTransactionCosts_b9d2d8b1-15ad-4d4d-bb84-6d23e6edb11c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_46b0f089-b46b-414f-b2d9-803466a90360" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_46b0f089-b46b-414f-b2d9-803466a90360" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_605b2e59-22ae-4e50-b1b6-923edaaf0bff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_605b2e59-22ae-4e50-b1b6-923edaaf0bff" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_f8709475-bcd8-4396-a797-68d4aff329a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_30c83ebb-d3cb-41c7-a26b-d128918d5ca0" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_f8709475-bcd8-4396-a797-68d4aff329a7" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofBasicandDilutedNetLossIncomePerShareDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofBasicandDilutedNetLossIncomePerShareDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofBasicandDilutedNetLossIncomePerShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasicLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable_40758921-09de-4667-b39c-0e6364636e9d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:to="loc_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable_40758921-09de-4667-b39c-0e6364636e9d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_684f71f4-fc78-4b16-9536-09fb29ad1777" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable_40758921-09de-4667-b39c-0e6364636e9d" xlink:to="loc_us-gaap_StatementClassOfStockAxis_684f71f4-fc78-4b16-9536-09fb29ad1777" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_684f71f4-fc78-4b16-9536-09fb29ad1777_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_684f71f4-fc78-4b16-9536-09fb29ad1777" xlink:to="loc_us-gaap_ClassOfStockDomain_684f71f4-fc78-4b16-9536-09fb29ad1777_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_d44c5bf5-e4a9-44b8-8612-bb4cd883dc9d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_684f71f4-fc78-4b16-9536-09fb29ad1777" xlink:to="loc_us-gaap_ClassOfStockDomain_d44c5bf5-e4a9-44b8-8612-bb4cd883dc9d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_394f5e5f-7b83-45d6-a4a3-5c70816c9a16" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_d44c5bf5-e4a9-44b8-8612-bb4cd883dc9d" xlink:to="loc_us-gaap_CommonClassAMember_394f5e5f-7b83-45d6-a4a3-5c70816c9a16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_f88d5b88-e8f9-4775-a985-7a90b7655033" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_d44c5bf5-e4a9-44b8-8612-bb4cd883dc9d" xlink:to="loc_us-gaap_CommonClassBMember_f88d5b88-e8f9-4775-a985-7a90b7655033" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_NumeratorAbstract_ebd7946a-3228-4889-af05-141bde04ef30" xlink:href="mq-20250930.xsd#mq_NumeratorAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:to="loc_mq_NumeratorAbstract_ebd7946a-3228-4889-af05-141bde04ef30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic_5ecd0067-93b4-4b70-ad72-8443434d467a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mq_NumeratorAbstract_ebd7946a-3228-4889-af05-141bde04ef30" xlink:to="loc_us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic_5ecd0067-93b4-4b70-ad72-8443434d467a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted_eff0e29f-fd50-4d1a-985e-2c63283f079c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mq_NumeratorAbstract_ebd7946a-3228-4889-af05-141bde04ef30" xlink:to="loc_us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted_eff0e29f-fd50-4d1a-985e-2c63283f079c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_DenominatorAbstract_35192d2e-b867-43f0-a12d-6bc33f984917" xlink:href="mq-20250930.xsd#mq_DenominatorAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:to="loc_mq_DenominatorAbstract_35192d2e-b867-43f0-a12d-6bc33f984917" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_d8c4e598-f494-4c22-882e-edc1e447a435" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mq_DenominatorAbstract_35192d2e-b867-43f0-a12d-6bc33f984917" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_d8c4e598-f494-4c22-882e-edc1e447a435" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_dc58cae5-bc32-4f5f-b264-398dd09f2dff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mq_DenominatorAbstract_35192d2e-b867-43f0-a12d-6bc33f984917" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_dc58cae5-bc32-4f5f-b264-398dd09f2dff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_1d1018f6-476b-45db-b9f3-983ef5752f1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mq_DenominatorAbstract_35192d2e-b867-43f0-a12d-6bc33f984917" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_1d1018f6-476b-45db-b9f3-983ef5752f1e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_baadbfbb-b1cd-415e-a688-e3f53daebc73" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_baadbfbb-b1cd-415e-a688-e3f53daebc73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_1cb19dcb-4d39-4c9c-9a69-4f0ea50aa4ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems_4af3b139-347e-4442-8756-dd29285defe5" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_1cb19dcb-4d39-4c9c-9a69-4f0ea50aa4ef" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofAntidilutiveSecuritiesDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofAntidilutiveSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/NetLossIncomePerShareAttributabletoCommonStockholdersScheduleofAntidilutiveSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7f8e6b09-9195-422a-affb-c4e59183821a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_ea17a0c6-f5b0-48c9-ba4c-d7ff8c0c1bf2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7f8e6b09-9195-422a-affb-c4e59183821a" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_ea17a0c6-f5b0-48c9-ba4c-d7ff8c0c1bf2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_444a7cfe-3204-4612-a5ae-e362b0897b6f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_ea17a0c6-f5b0-48c9-ba4c-d7ff8c0c1bf2" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_444a7cfe-3204-4612-a5ae-e362b0897b6f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_444a7cfe-3204-4612-a5ae-e362b0897b6f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_444a7cfe-3204-4612-a5ae-e362b0897b6f" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_444a7cfe-3204-4612-a5ae-e362b0897b6f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_9a16a3b7-8656-4f8a-8760-ed734f1c4fa8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_444a7cfe-3204-4612-a5ae-e362b0897b6f" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_9a16a3b7-8656-4f8a-8760-ed734f1c4fa8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_WarrantsToPurchaseClassBCommonStockMember_5decfcb9-d78a-4b6b-a0ec-39c8471469c7" xlink:href="mq-20250930.xsd#mq_WarrantsToPurchaseClassBCommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_9a16a3b7-8656-4f8a-8760-ed734f1c4fa8" xlink:to="loc_mq_WarrantsToPurchaseClassBCommonStockMember_5decfcb9-d78a-4b6b-a0ec-39c8471469c7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_7783e0e1-97aa-4651-8b55-e75b0a832832" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_9a16a3b7-8656-4f8a-8760-ed734f1c4fa8" xlink:to="loc_us-gaap_EmployeeStockOptionMember_7783e0e1-97aa-4651-8b55-e75b0a832832" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_82a672f0-63ba-4f0b-aebe-d76ee2c22426" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_ea17a0c6-f5b0-48c9-ba4c-d7ff8c0c1bf2" xlink:to="loc_us-gaap_StatementClassOfStockAxis_82a672f0-63ba-4f0b-aebe-d76ee2c22426" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_82a672f0-63ba-4f0b-aebe-d76ee2c22426_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_82a672f0-63ba-4f0b-aebe-d76ee2c22426" xlink:to="loc_us-gaap_ClassOfStockDomain_82a672f0-63ba-4f0b-aebe-d76ee2c22426_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_df52b463-6b9d-4ab2-b6a9-6c04c71509e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_82a672f0-63ba-4f0b-aebe-d76ee2c22426" xlink:to="loc_us-gaap_ClassOfStockDomain_df52b463-6b9d-4ab2-b6a9-6c04c71509e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_e8425287-e1c6-4297-bf37-b85f8a12b267" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_df52b463-6b9d-4ab2-b6a9-6c04c71509e2" xlink:to="loc_us-gaap_CommonClassAMember_e8425287-e1c6-4297-bf37-b85f8a12b267" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_b4b989ca-260a-411b-98e0-3e2e7dc152a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_df52b463-6b9d-4ab2-b6a9-6c04c71509e2" xlink:to="loc_us-gaap_CommonClassBMember_b4b989ca-260a-411b-98e0-3e2e7dc152a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_9f7d4cb5-3388-4fec-bc3c-c2ec09eb5fd6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7f8e6b09-9195-422a-affb-c4e59183821a" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_9f7d4cb5-3388-4fec-bc3c-c2ec09eb5fd6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/ConcentrationRisksandSignificantCustomersDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#ConcentrationRisksandSignificantCustomersDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/ConcentrationRisksandSignificantCustomersDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_306ba9e6-fadb-46ac-8426-f878d98c8128" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_306ba9e6-fadb-46ac-8426-f878d98c8128" xlink:to="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_e623c454-b9e2-46a0-9be4-73d9c65ca43e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_e623c454-b9e2-46a0-9be4-73d9c65ca43e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_e623c454-b9e2-46a0-9be4-73d9c65ca43e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_e623c454-b9e2-46a0-9be4-73d9c65ca43e" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_e623c454-b9e2-46a0-9be4-73d9c65ca43e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8e84d440-c5f5-471c-9e23-cc7bc473a5e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_e623c454-b9e2-46a0-9be4-73d9c65ca43e" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8e84d440-c5f5-471c-9e23-cc7bc473a5e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_DebtSecuritiesAvailableForSaleMember_7f6d2da1-b3e6-46d1-89c6-1a97c73c44f0" xlink:href="mq-20250930.xsd#mq_DebtSecuritiesAvailableForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8e84d440-c5f5-471c-9e23-cc7bc473a5e7" xlink:to="loc_mq_DebtSecuritiesAvailableForSaleMember_7f6d2da1-b3e6-46d1-89c6-1a97c73c44f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableMember_fa0a4fb5-a051-465a-828e-c643f7bcedfc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8e84d440-c5f5-471c-9e23-cc7bc473a5e7" xlink:to="loc_us-gaap_AccountsReceivableMember_fa0a4fb5-a051-465a-828e-c643f7bcedfc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_4fb56cf9-ae5d-4131-ae9a-06cf1733de70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8e84d440-c5f5-471c-9e23-cc7bc473a5e7" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_4fb56cf9-ae5d-4131-ae9a-06cf1733de70" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_cc2c39aa-3228-44ed-b7b9-3a74f522db8a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_cc2c39aa-3228-44ed-b7b9-3a74f522db8a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_cc2c39aa-3228-44ed-b7b9-3a74f522db8a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_cc2c39aa-3228-44ed-b7b9-3a74f522db8a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_cc2c39aa-3228-44ed-b7b9-3a74f522db8a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_650749c7-d893-487e-bcb7-1d96ba7568fe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_cc2c39aa-3228-44ed-b7b9-3a74f522db8a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_650749c7-d893-487e-bcb7-1d96ba7568fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditConcentrationRiskMember_4dae6d16-bf9a-4f42-99ef-3896ca9966d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_650749c7-d893-487e-bcb7-1d96ba7568fe" xlink:to="loc_us-gaap_CreditConcentrationRiskMember_4dae6d16-bf9a-4f42-99ef-3896ca9966d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_7d526331-169a-4ddb-9bfd-6dcd4051bf84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_650749c7-d893-487e-bcb7-1d96ba7568fe" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_7d526331-169a-4ddb-9bfd-6dcd4051bf84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_d44f63d6-a467-4ebf-aa15-2265c1a7e22e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:to="loc_us-gaap_FinancialInstrumentAxis_d44f63d6-a467-4ebf-aa15-2265c1a7e22e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d44f63d6-a467-4ebf-aa15-2265c1a7e22e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_d44f63d6-a467-4ebf-aa15-2265c1a7e22e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d44f63d6-a467-4ebf-aa15-2265c1a7e22e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6d2b5196-dfd1-454c-8546-c67b1d0a8faa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_d44f63d6-a467-4ebf-aa15-2265c1a7e22e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6d2b5196-dfd1-454c-8546-c67b1d0a8faa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_MarketableSecuritiesMember_fd9e7399-67ca-4504-99be-56f06189e986" xlink:href="mq-20250930.xsd#mq_MarketableSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6d2b5196-dfd1-454c-8546-c67b1d0a8faa" xlink:to="loc_mq_MarketableSecuritiesMember_fd9e7399-67ca-4504-99be-56f06189e986" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_ed68eefc-8573-4c81-b5a0-f054f471d749" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_ed68eefc-8573-4c81-b5a0-f054f471d749" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_ed68eefc-8573-4c81-b5a0-f054f471d749_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_ed68eefc-8573-4c81-b5a0-f054f471d749" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_ed68eefc-8573-4c81-b5a0-f054f471d749_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_584a1fd5-638b-459c-a8ed-e1a1aba96e70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_ed68eefc-8573-4c81-b5a0-f054f471d749" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_584a1fd5-638b-459c-a8ed-e1a1aba96e70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_SuttonBankMember_6db15987-0875-459c-af36-cb6a107297f5" xlink:href="mq-20250930.xsd#mq_SuttonBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_584a1fd5-638b-459c-a8ed-e1a1aba96e70" xlink:to="loc_mq_SuttonBankMember_6db15987-0875-459c-af36-cb6a107297f5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_1327c7a1-d902-48e9-a725-b23f9d909fdd" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9fb5e288-73d3-4c50-8117-a0e0ea9ca629" xlink:to="loc_srt_MajorCustomersAxis_1327c7a1-d902-48e9-a725-b23f9d909fdd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_1327c7a1-d902-48e9-a725-b23f9d909fdd_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_1327c7a1-d902-48e9-a725-b23f9d909fdd" xlink:to="loc_srt_NameOfMajorCustomerDomain_1327c7a1-d902-48e9-a725-b23f9d909fdd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_1327c7a1-d902-48e9-a725-b23f9d909fdd" xlink:to="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_Customer1Member_13220d91-0555-4c4d-a994-627df7c390d8" xlink:href="mq-20250930.xsd#mq_Customer1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:to="loc_mq_Customer1Member_13220d91-0555-4c4d-a994-627df7c390d8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_Customer2Member_3f1c54db-c913-4677-8e3f-d89fe2b5136f" xlink:href="mq-20250930.xsd#mq_Customer2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:to="loc_mq_Customer2Member_3f1c54db-c913-4677-8e3f-d89fe2b5136f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_Customer3Member_a93cbce4-2363-42ca-b582-5039642be4bf" xlink:href="mq-20250930.xsd#mq_Customer3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:to="loc_mq_Customer3Member_a93cbce4-2363-42ca-b582-5039642be4bf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_Customer4Member_ce3fe3c6-a377-4df3-b51d-c540d40d443e" xlink:href="mq-20250930.xsd#mq_Customer4Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_47a45669-6f9b-41ea-9c50-e338d61f8f3e" xlink:to="loc_mq_Customer4Member_ce3fe3c6-a377-4df3-b51d-c540d40d443e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_dd20fe5d-928d-40b1-9b00-ea5edf9317e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_306ba9e6-fadb-46ac-8426-f878d98c8128" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_dd20fe5d-928d-40b1-9b00-ea5edf9317e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_bff09a77-de84-458a-b4fb-fbb86f96dcd5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_306ba9e6-fadb-46ac-8426-f878d98c8128" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_bff09a77-de84-458a-b4fb-fbb86f96dcd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_NumberOfIssuingBankPaymentSettlementThroughTransaction_09738200-9d9b-4c96-a8f6-dc7c4f602ee2" xlink:href="mq-20250930.xsd#mq_NumberOfIssuingBankPaymentSettlementThroughTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_306ba9e6-fadb-46ac-8426-f878d98c8128" xlink:to="loc_mq_NumberOfIssuingBankPaymentSettlementThroughTransaction_09738200-9d9b-4c96-a8f6-dc7c4f602ee2" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/SegmentInformationScheduleofInformationUsedbytheCODMDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#SegmentInformationScheduleofInformationUsedbytheCODMDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/SegmentInformationScheduleofInformationUsedbytheCODMDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fdbf6938-43d7-4783-9a31-4398c96e5d7a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fdbf6938-43d7-4783-9a31-4398c96e5d7a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_62338371-753a-40b5-aa3b-163c129e112b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fdbf6938-43d7-4783-9a31-4398c96e5d7a" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_62338371-753a-40b5-aa3b-163c129e112b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_62338371-753a-40b5-aa3b-163c129e112b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_62338371-753a-40b5-aa3b-163c129e112b" xlink:to="loc_us-gaap_SegmentDomain_62338371-753a-40b5-aa3b-163c129e112b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5af3f1db-e2d5-44ec-b8a9-8b3e1317b6a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_62338371-753a-40b5-aa3b-163c129e112b" xlink:to="loc_us-gaap_SegmentDomain_5af3f1db-e2d5-44ec-b8a9-8b3e1317b6a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_ReportableSegmentMember_3123f08e-11a7-4d10-9bce-d049a55e965c" xlink:href="mq-20250930.xsd#mq_ReportableSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5af3f1db-e2d5-44ec-b8a9-8b3e1317b6a4" xlink:to="loc_mq_ReportableSegmentMember_3123f08e-11a7-4d10-9bce-d049a55e965c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_e3b915b2-b225-4964-85d7-bba4b01bd38b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_e3b915b2-b225-4964-85d7-bba4b01bd38b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenue_34556166-211a-41dd-83bc-14923fa19ad5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_CostOfRevenue_34556166-211a-41dd-83bc-14923fa19ad5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_0d62c1c9-0113-4366-8c41-200f76cac115" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_GrossProfit_0d62c1c9-0113-4366-8c41-200f76cac115" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CompensationExpenseExcludingCostOfGoodAndServiceSold_2f1fbed4-1d56-4c87-99b7-4b7d6b015f04" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CompensationExpenseExcludingCostOfGoodAndServiceSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_CompensationExpenseExcludingCostOfGoodAndServiceSold_2f1fbed4-1d56-4c87-99b7-4b7d6b015f04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_d55ac31c-5105-489a-b0d1-ecf968faf194" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_d55ac31c-5105-489a-b0d1-ecf968faf194" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommunicationsAndInformationTechnology_2d003981-2790-44cf-b7ad-c25c703b0c22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommunicationsAndInformationTechnology"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_CommunicationsAndInformationTechnology_2d003981-2790-44cf-b7ad-c25c703b0c22" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfessionalFees_fe5fbaa3-550d-4a82-989c-af9af160b0c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfessionalFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_ProfessionalFees_fe5fbaa3-550d-4a82-989c-af9af160b0c2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyNet_1c211265-0d8e-4898-af8e-0cdfec5e2eb7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OccupancyNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_OccupancyNet_1c211265-0d8e-4898-af8e-0cdfec5e2eb7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_cd0bc444-7075-4937-b3d7-1b759e3f928b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_cd0bc444-7075-4937-b3d7-1b759e3f928b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketingAndAdvertisingExpense_4a77723f-a7ea-4e78-812c-e738730aacac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketingAndAdvertisingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_MarketingAndAdvertisingExpense_4a77723f-a7ea-4e78-812c-e738730aacac" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCostAndExpenseOperating_c4ee231d-7362-4aa8-b7e1-c5a56a85c8ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostAndExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_OtherCostAndExpenseOperating_c4ee231d-7362-4aa8-b7e1-c5a56a85c8ef" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_ExecutiveChairmanLongTermPerformanceAward_e843b8d5-9e3d-4e65-b4ef-be4de5b0c08f" xlink:href="mq-20250930.xsd#mq_ExecutiveChairmanLongTermPerformanceAward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_mq_ExecutiveChairmanLongTermPerformanceAward_e843b8d5-9e3d-4e65-b4ef-be4de5b0c08f" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_4ad0469b-012a-4eb1-9ea6-f90974b3f56c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_OperatingIncomeLoss_4ad0469b-012a-4eb1-9ea6-f90974b3f56c" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOther_cf3d4f60-a4cb-4c73-979c-2c90bdb1acdb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_InterestIncomeOther_cf3d4f60-a4cb-4c73-979c-2c90bdb1acdb" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonrecurringIncomeExpense_28f8fdf1-ed1f-45ae-bf4f-0c469832239f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonrecurringIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_OtherNonrecurringIncomeExpense_28f8fdf1-ed1f-45ae-bf4f-0c469832239f" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_64048b21-cab8-4518-b08a-a5652ba73eb9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_64048b21-cab8-4518-b08a-a5652ba73eb9" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_54e47e89-231a-4f15-a5b3-fa7c4e07c52e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4903dc96-28ff-4832-b60e-c6507992b97c" xlink:to="loc_us-gaap_NetIncomeLoss_54e47e89-231a-4f15-a5b3-fa7c4e07c52e" xlink:type="arc" order="16"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.marqeta.com/role/SegmentInformationNarrativeDetails" xlink:type="simple" xlink:href="mq-20250930.xsd#SegmentInformationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.marqeta.com/role/SegmentInformationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_8cf85b60-37cd-41bc-aede-3eb328de20e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fd54a68a-b613-4a89-8905-d338c720d167" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_8cf85b60-37cd-41bc-aede-3eb328de20e7" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fd54a68a-b613-4a89-8905-d338c720d167" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_5b4c21db-0b31-4479-a74f-da451a4df40d" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fd54a68a-b613-4a89-8905-d338c720d167" xlink:to="loc_srt_StatementGeographicalAxis_5b4c21db-0b31-4479-a74f-da451a4df40d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_5b4c21db-0b31-4479-a74f-da451a4df40d_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_5b4c21db-0b31-4479-a74f-da451a4df40d" xlink:to="loc_srt_SegmentGeographicalDomain_5b4c21db-0b31-4479-a74f-da451a4df40d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_eae33f7b-0aa2-4066-a893-b9fc481c09ee" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_5b4c21db-0b31-4479-a74f-da451a4df40d" xlink:to="loc_srt_SegmentGeographicalDomain_eae33f7b-0aa2-4066-a893-b9fc481c09ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonUsMember_7ee346fb-8e61-4c79-aa06-157a9f95cf46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_eae33f7b-0aa2-4066-a893-b9fc481c09ee" xlink:to="loc_us-gaap_NonUsMember_7ee346fb-8e61-4c79-aa06-157a9f95cf46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_267cdc78-c6a0-409d-8ea7-df59c1aef35f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fd54a68a-b613-4a89-8905-d338c720d167" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_267cdc78-c6a0-409d-8ea7-df59c1aef35f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_267cdc78-c6a0-409d-8ea7-df59c1aef35f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_267cdc78-c6a0-409d-8ea7-df59c1aef35f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_267cdc78-c6a0-409d-8ea7-df59c1aef35f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_68b0448c-3913-4328-8e39-ede325a2f73c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_267cdc78-c6a0-409d-8ea7-df59c1aef35f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_68b0448c-3913-4328-8e39-ede325a2f73c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_a7754b92-41d3-4530-903a-7cc2d6b0b4d3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_68b0448c-3913-4328-8e39-ede325a2f73c" xlink:to="loc_us-gaap_SalesRevenueNetMember_a7754b92-41d3-4530-903a-7cc2d6b0b4d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_c72569f1-5bcb-40fc-b379-2e675c097f68" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fd54a68a-b613-4a89-8905-d338c720d167" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_c72569f1-5bcb-40fc-b379-2e675c097f68" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_c72569f1-5bcb-40fc-b379-2e675c097f68_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_c72569f1-5bcb-40fc-b379-2e675c097f68" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_c72569f1-5bcb-40fc-b379-2e675c097f68_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_49c48dba-1d3d-4e71-87de-a8e62d5c584c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_c72569f1-5bcb-40fc-b379-2e675c097f68" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_49c48dba-1d3d-4e71-87de-a8e62d5c584c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_bb6b7dfa-2210-4763-9333-ef7d8ed73b02" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_49c48dba-1d3d-4e71-87de-a8e62d5c584c" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_bb6b7dfa-2210-4763-9333-ef7d8ed73b02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_c158cd2a-ce17-4e59-a463-3d5d81c5078a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_8cf85b60-37cd-41bc-aede-3eb328de20e7" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_c158cd2a-ce17-4e59-a463-3d5d81c5078a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_AccruedLiabilitiesAndOtherLiabilitiesCurrent_9b802ab0-0795-4a73-8f47-fe04079a7b01" xlink:href="mq-20250930.xsd#mq_AccruedLiabilitiesAndOtherLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="loc_mq_AccruedLiabilitiesAndOtherLiabilitiesCurrent_9b802ab0-0795-4a73-8f47-fe04079a7b01" xlink:type="arc" order="41"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_RahulShahMember_8a4650b0-0826-4282-987f-2eace96b7f91" xlink:href="mq-20250930.xsd#mq_RahulShahMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_mq_RahulShahMember_8a4650b0-0826-4282-987f-2eace96b7f91" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_MarthaCummingsMember_b1f6db1f-25ce-4434-a259-69a067aebc2b" xlink:href="mq-20250930.xsd#mq_MarthaCummingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_mq_MarthaCummingsMember_b1f6db1f-25ce-4434-a259-69a067aebc2b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_NajumaAtkinsonMember_9c84fd8c-a5bd-4145-b01b-e846a32150f5" xlink:href="mq-20250930.xsd#mq_NajumaAtkinsonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_mq_NajumaAtkinsonMember_9c84fd8c-a5bd-4145-b01b-e846a32150f5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_mq_JasonGardnerMember_81f276ca-35e0-4582-a31c-e3608d25681e" xlink:href="mq-20250930.xsd#mq_JasonGardnerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_mq_JasonGardnerMember_81f276ca-35e0-4582-a31c-e3608d25681e" xlink:type="arc" order="5"/>
  </link:definitionLink>
</link:linkbase>
