- blackjack [blak′jak΄]n.[see JACK]1. a large beer mug, formerly made of leather coated with tar2. BLACK FLAG☆ 3. a small, leather-covered bludgeon with a flexible handle☆ 4. a SE U.S. scrub oak (Quercus marilandica) with fan-shaped leaves5.☆ a) a gambling game at cards in which any player wins who gets cards totaling twenty-one points or less while the dealer gets either a smaller total or a total exceeding twenty-one pointsb) a combination of an ace and a face card or ten, equaling 21 points in this game6. sphalerite, esp. a dark variety: also written black jackvt.1. to hit with a blackjack2. to force (a person) to do something by threatening, as if with a blackjack
English World dictionary. V. Neufeldt. 2014.