The poker term double up is a popular phrase in no-limit games and refers to doubling your bankroll after going all-in against your opponent and winning the hand.
Double Up Poker Example:
Let’s say you’re on your last 200 chips, while your opponent has 1,500. After doubling up and winning the hand, you would have 400 chips while they would have 1,100. If you double up two times in a row, you can completely turn the tables and have more chips than your opponent.