Full explanation — Semi-Bluff
A semi-bluff is a bet or raise made with a hand that is currently behind but holds significant outs, such as a flush or straight draw. Unlike a pure bluff, you have two ways to win: the opponent folds immediately, or they call and you still improve to the best hand on a later street. Because of this double chance, semi-bluffing is considered the most profitable form of aggression in poker, and it forms the backbone of modern aggressive strategy on the flop and turn.