Webster’s Revised Unabridged Dictionary · 1913
Postdate
Post′date′ (pōst′dāt′), v. t. [imp. & p. p. Postdated; p. pr. & vb. n. Postdating.] [Pref. post- + date.] 1. To date after the real time; as, to postdate a contract, that is, to date it later than the time when it was in fact made.
2. To affix a date to after the event.
Post′date′, a. Made or done after the date assigned.
Of these [predictions] some were postdate; cunningly made after the thing came to pass. Fuller.
Post′date′, n. A date put to a bill of exchange or other paper, later than that when it was actually made.