1. A leather-covered bludgeon with a short, flexible shaft or strap, used as a hand weapon.
2. the blackjack oak.
3. games A card game in which the object is to accumulate cards with a higher count than that of the dealer but not exceeding 21. also called twenty-one, vingt-et-un.
4. sphalerite.
5. to hit or beat with a leather-covered bludgeon.
6. to coerce by threats.

1. A common gambling card game in casinos, where the object is to get as close to 21 without going over.
2. A hand in the game of blackjack consisting of a face card and an ace.
3. the flag (i.e., a jack) traditionally flown by pirate ships; popularly thought to be a white skull and crossed bones on a black field (the jolly roger). in older literature sometimes spelled "black jack".
4. a small, flat, blunt, usually leather-covered instrument loaded with heavy material such as lead or ball bearings.
5. a type of weed, Bidens pilosa, in the family Compositae.
6. to strike with a blackjack or similar weapon.

1. exert pressure on someone through threats
2. a flag usually bearing a white skull and crossbones on a black background; indicates a pirate ship
3. a gambling game using cards; the object is to hold cards having a higher count than those dealt to the banker up to but not exceeding 21
4. a piece of metal covered by leather with a flexible handle; used for hitting people
5. a common scrubby deciduous tree of central and southeastern united states having dark bark and broad three-lobed (club-shaped) leaves; tends to form dense thickets