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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:431a97cc-26c0-4217-b0c3-80955a3dfe90,g:b0d049d9-5267-4627-96f6-ed2793bcca55-->
<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://sonder.com/role/Cover" xlink:type="simple" xlink:href="son-20251107.xsd#Cover"/>
  <link:definitionLink xlink:role="http://sonder.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_6a0d492e-82b9-4026-9ef8-6925c94d18ee" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_DocumentInformationTable_6a0d492e-82b9-4026-9ef8-6925c94d18ee" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_c4709568-a71a-4fe0-b4db-0ca59f3ad229" 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_DocumentInformationTable_6a0d492e-82b9-4026-9ef8-6925c94d18ee" xlink:to="loc_us-gaap_StatementClassOfStockAxis_c4709568-a71a-4fe0-b4db-0ca59f3ad229" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_c4709568-a71a-4fe0-b4db-0ca59f3ad229_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_c4709568-a71a-4fe0-b4db-0ca59f3ad229" xlink:to="loc_us-gaap_ClassOfStockDomain_c4709568-a71a-4fe0-b4db-0ca59f3ad229_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_3dcd730f-7b4b-4659-bd1e-3d7bb081e405" 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_c4709568-a71a-4fe0-b4db-0ca59f3ad229" xlink:to="loc_us-gaap_ClassOfStockDomain_3dcd730f-7b4b-4659-bd1e-3d7bb081e405" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_836a62bd-2c7b-4757-b25d-442f49dfbad3" 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_ClassOfStockDomain_3dcd730f-7b4b-4659-bd1e-3d7bb081e405" xlink:to="loc_us-gaap_CommonStockMember_836a62bd-2c7b-4757-b25d-442f49dfbad3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_67126157-e300-4cb3-9686-23ac11390a9a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_3dcd730f-7b4b-4659-bd1e-3d7bb081e405" xlink:to="loc_us-gaap_WarrantMember_67126157-e300-4cb3-9686-23ac11390a9a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_26328ed3-b748-4455-997d-2226672d3a37" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_DocumentType_26328ed3-b748-4455-997d-2226672d3a37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_11f7f6b9-87bf-4b7c-8084-a05711e4c40d" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_DocumentPeriodEndDate_11f7f6b9-87bf-4b7c-8084-a05711e4c40d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_3f89b86c-5ae3-47a2-836a-98a3dfcd2d58" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityRegistrantName_3f89b86c-5ae3-47a2-836a-98a3dfcd2d58" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_407964b6-c318-4737-8f70-4626a10e4994" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityIncorporationStateCountryCode_407964b6-c318-4737-8f70-4626a10e4994" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_09fbc79c-fd36-4cc1-a270-d1d391b5d1cb" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityFileNumber_09fbc79c-fd36-4cc1-a270-d1d391b5d1cb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_e114c17a-c746-4932-b4ea-5b649c59350b" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityTaxIdentificationNumber_e114c17a-c746-4932-b4ea-5b649c59350b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine3_4545ca93-f149-476b-9260-5082d32f25d9" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressAddressLine3_4545ca93-f149-476b-9260-5082d32f25d9" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_7b32953b-b122-4f12-b183-0320f714ecef" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressAddressLine2_7b32953b-b122-4f12-b183-0320f714ecef" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_c127d695-2293-43ea-97a1-efd40c078df6" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressAddressLine1_c127d695-2293-43ea-97a1-efd40c078df6" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_1f90abff-c994-43c5-aa7e-ca471396952e" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressCityOrTown_1f90abff-c994-43c5-aa7e-ca471396952e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_1e43ed20-90f0-4400-9e2d-665060135629" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressStateOrProvince_1e43ed20-90f0-4400-9e2d-665060135629" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_e1fc0ea1-a7dd-42c5-bf6c-efc609f9830d" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityAddressPostalZipCode_e1fc0ea1-a7dd-42c5-bf6c-efc609f9830d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_5f35ea3c-a19f-48a5-a25a-249132536af0" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_CityAreaCode_5f35ea3c-a19f-48a5-a25a-249132536af0" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_75843aaf-d4d8-4fc7-af7c-334eead29a5a" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_LocalPhoneNumber_75843aaf-d4d8-4fc7-af7c-334eead29a5a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_7526274b-fddc-4e9a-be7f-12e1ef8d38f7" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_WrittenCommunications_7526274b-fddc-4e9a-be7f-12e1ef8d38f7" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_788810a1-eaf9-493d-a22c-8dfa4cb53f53" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_SolicitingMaterial_788810a1-eaf9-493d-a22c-8dfa4cb53f53" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_04ba398c-8d44-4734-bc0c-e4a09cb7180e" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_PreCommencementTenderOffer_04ba398c-8d44-4734-bc0c-e4a09cb7180e" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_c4b27a34-e634-4cb0-8985-48063778f99b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_c4b27a34-e634-4cb0-8985-48063778f99b" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_45d8fe44-5670-48b7-9e1a-cb4111616c36" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_Security12bTitle_45d8fe44-5670-48b7-9e1a-cb4111616c36" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_a55c80fd-4bd1-49c8-addf-1eed3bf5330c" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_TradingSymbol_a55c80fd-4bd1-49c8-addf-1eed3bf5330c" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_390a85f9-2a01-4579-9444-5cd3723cb7ce" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_SecurityExchangeName_390a85f9-2a01-4579-9444-5cd3723cb7ce" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_2880c67e-2873-4a54-b211-3e8a5a01495e" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityEmergingGrowthCompany_2880c67e-2873-4a54-b211-3e8a5a01495e" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityExTransitionPeriod_666bc769-1d5d-4e64-8f79-372ffa406107" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityExTransitionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityExTransitionPeriod_666bc769-1d5d-4e64-8f79-372ffa406107" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_fd76303f-0f56-49d6-85a8-db0f26d6cc1e" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_AmendmentFlag_fd76303f-0f56-49d6-85a8-db0f26d6cc1e" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_b35678e3-6d37-4890-a794-d23776f86d9a" 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_DocumentInformationLineItems_56c9b1b2-8d88-4893-9217-a80c2ed6de74" xlink:to="loc_dei_EntityCentralIndexKey_b35678e3-6d37-4890-a794-d23776f86d9a" xlink:type="arc" order="24"/>
  </link:definitionLink>
</link:linkbase>
