meaning of postdate
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.
3. Made or done after the date assigned.
4. A date put to a bill of exchange or other paper, later than that when it was actually made.
5. establish something as being later relative to something else