A poker double up occurs when a player doubles their entire stack in a single hand.
For example, let’s say you’re playing in a poker tournament and have just about 5,000 chips in your stack. The blinds are 250/500, so you’re losing a sizable chunk every time you decide to play a hand.
During one hand, you decide it’s the best opportunity to shove, and the board runs out in your favor.
Thanks to the blinds, you’ve more than doubled your previous chip stack and now have over 10,000 chips. This means you’ve just successfully doubled up.