A prop bet in poker is a side bet that’s made outside of the standard rules of the game. It’s not tied to the game’s outcome and often relates to a significant achievement or a difficult mental or physical challenge.
Prop Bet Poker Example:
In 2016, Vanessa Selbst offered Jason Mercier a 180 to 1 prop bet that he wouldn't win three bracelets during that year’s WSOP. Mercier would have won a whopping $1.8 million, but he finished the series with two bracelets and one second-place position.