backer Play /ˈbækər/nounA person, institution, or country that supports someone or something, especially financially.$3.3 million was provided by the project’s backerssponsor,investor,subsidizer,underwriter,promoter,financier,patron,benefactor,benefactress,guarantor,supporter,friend SYNONYMS benefactorbenefactressfinancierfriendguarantorinvestorpatronpromotersponsorsubsidizersupporterunderwriter