blackjacks

1. 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 thicketsSynonyms: Quercus marilandica, blackjack, blackjack oak, jack oak

2. a piece of metal covered by leather with a flexible handle; used for hitting peopleSynonyms: blackjack, cosh, sap

3. a flag usually bearing a white skull and crossbones on a black background; indicates a pirate shipSynonyms: Jolly Roger, black flag, blackjack, pirate flag

4. 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 21Synonyms: blackjack, twenty-one, vingt-et-un