bull pen


bull′ pen`

or bull′pen`,


n. 1. a. a place where relief pitchers warm up during a baseball game. b. the relief pitchers on a team. 2. Informal. a. a large cell for the temporary detention of prisoners. b. any temporary or crowded quarters, as sleeping quarters in a lumber camp. 3. a pen for bulls. [1920–25, Amer. (definition 1)]