*black-jack*

n. 1. (Min.) A name given by English miners to sphalerite, or zinc blende; -- called also false galena. See Blende. [ 1913 Webster ]

2. Caramel or burnt sugar, used to color wines, spirits, ground coffee, etc. [ 1913 Webster ]

3. A large leather vessel for beer, etc. [ Obs. ] [ 1913 Webster ]

4. (Bot.) The Quercus nigra, or barren oak. [ 1913 Webster ]

5. The ensign of a pirate. [ 1913 Webster ]