The prefix post- means “after” or “coming after.” When you see post- at the beginning of a word, it tells you that something happens later in time or comes after something else.

A postscript is a message added after the main part of a letter (often abbreviated as P.S.). A post-test is a test given after you've learned the material, to see how much you've mastered. The postseason in sports comes after the regular season ends.

You'll see this prefix everywhere once you start noticing it. Post-war means after a war. Postgraduate refers to education after graduating from college.

The opposite of post- is pre-, which means “before.” So pre-game happens before the game, while post-game happens after. Understanding post- helps you decode dozens of words: if something is postmodern, it comes after the modern period. If an event is post-election, it happens after the election.