A lot vs. Alot: 9 Grammatical Pitfalls
word-forming element meaning "after," from Latin post "behind, after, afterward," from *pos-ti (cf. Arcadian pos, Doric poti "toward, to, near, close by;" Old Church Slavonic po "behind, after," pozdu "late;" Lithuanian pas "at, by"), from PIE *apo- (cf. Greek apo "from," Latin ab "away from" see apo-).
After; later: postpartum.
Behind; posterior to: postaxial.
A prefix that means "after," as in postoperative, after an operation, or "behind," as in postnasal, behind the nose or nasal passages.