A very strong hand that almost never loses, such as a set or a made flush.
Used often in Limit games, it usually means two pair or better, a set (three of a kind from a pocket pair and one board card), or a made straight or flush. Example. With 8-8 on a K♠ 8♦ 3♣ board you have a set, a monster. With such a hand you don't need the opponent to fold, so make the amount they can pay as big as possible to get value (what you win from a strong hand).