CapThe cap is the last possible raise in a round or the upper limit on how much can be wagered in one hand. Rounds are usually capped at 3,4, or 5 raises per round. The last raise is the cap.
There is a particular form of pot- and no-limit game where a cap limits how much one particular player can wager over all the betting rounds. If he reaches this limit, he is considered all-in.