antedate v.

Proto-Indo-European root meaning "front, forehead," with derivatives meaning "in front of, before; end." Also see *ambhi-.

It forms all or part of: advance; advantage; along; ancestor; ancient (adj.); answer; Antaeus; ante; ante-; ante meridiem; antecede; antecedent; antedate; antediluvian; ante-partum; antepenultimate; anterior; anti-; antic; anticipate; anticipation; antique; antler; avant-garde; elope; end; rampart; un- (2) prefix of reversal; until; vambrace; vamp (n.1) "upper of a shoe or boot;" vanguard.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit antah "end, border, boundary;" Hittite hanti "opposite;" Greek anta, anten "opposite," anti "over against, opposite, before;" Latin ante (prep., adv.) "before (in place or time), in front of, against;" Old Lithuanian anta "on to;" Gothic anda "along;" Old English and- "against;" German ent- "along, against."

c. 1400, daten, "to mark (a document) with a date," also "to assign to or indicate a date" (of an event), from date (n.1). Meaning "to mark as old-fashioned" is from 1895. Intransitive sense of "to have a date" is by 1850.

also back-date, "assign a date to earlier than the actual one," by 1881 (implied in back-dated), from back (adv.) + date (v.1). Compare antedate. Related: Backdated; backdating.