Pronunciation: (blak'jak"),[key] —n. 1. a short, leather-covered club, consisting of a heavy head on a flexible handle, used as a weapon.
2. Cards. a. twenty-one (def. 4).
b. Also callednatural. (in twenty-one) an ace together with a ten or a face card as the first two cards dealt.
c. a variety of twenty-one in which any player can become dealer.
3. See black flag (defs. 1, 2).
4. a small oak, Quercus marilandica, of the eastern U.S., having a nearly black bark and a wood of little value except for fuel.
5. a large drinking cup or jug for beer, ale, etc., originally made of leather coated externally with tar. Cf. bombard (def. 7).
6. caramel or burnt sugar for coloring spirits, vinegar, coffee, etc.
7. Mineral.a dark, iron-rich variety of sphalerite.
—v.t. 1. to strike or beat with a blackjack.
2. to compel by threat.