1640s, failer, "a failing, deficiency," also "act of failing," from Anglo-French failer, Old French falir "be lacking; not succeed" (see fail (v.)). The verb in Anglo-French used as a noun; ending altered 17c. in English to conform with words in -ure. Meaning "thing or person considered as a failure" is from 1837.[failure etymology, failure origin, 英语词源]