Green’s Dictionary of Slang

bull n.8

[bullet n.2 ]

1. in poker, an ace.

[US]Wentworth & Flexner DAS.

2. (drugs) one gram of pure cocaine.

[US]Africa News Service 29 Nov. [Internet] Each gram of pure cocaine (called a bull, short for bullet) cost him between Sh3,500 and Sh5,000 – depending on the exchange rate.