Rabbit hunting is poker slang that’s used to describe running out the rest of the hand even though the actual hand has concluded. Players generally ‘rabbit hunt’ to see if they would have made a particular hand or not.
Here’s an example: Let’s say you’re playing some no limit holdem. You raise before the flop and only one opponent calls. The flop comes and you bet. Your opponent folds, but asks the dealer to ‘rabbit hunt’. In this case, the dealer would deal the turn and the river to see how the hand would have turned out if your opponent called.
Rabbit hunting is generally frowned upon in live casinos, as it slows down the game and can discourage action. The practice is fairly common in home games, and is almost non-existent online.