To fail is defined as to be unsuccessful at something, to not do something you should, or to tell someone they were unsuccessful at something.(verb)
See fail in Webster's New World College Dictionary
Origin: ME failen < OFr faillir, to fail, miss < L fallere, to deceive, disappoint < IE base *ĝhwel-, to bend, deviate > Sans hválati, (he) loses the way, errs, Gr phēloein, to deceive
Origin: ME faile < OFr faile < the v.
See fail in American Heritage Dictionary 4
verb failed, fail·ing, fails verb, intransitive
Origin: Middle English failen
Origin: , from Old French faillir
Origin: , from Vulgar Latin *fallīre
Origin: , variant of Latin fallere, to deceive.
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