breaker
1. break.er \'bra--k*r\ n 1a: one that breaks 1b: a device or instrument that breaks; specif : a machine or plant for breaking rocks or crushing anthracite 2: a wave breaking into foam against the shore, a sandbank, or a rock 3: a strip of fabric under the tread of a tire for extra protection of the carcass 2. brea.ker \'bra--k*r\ n [by folk etymology fr. Sp barrica] : a small water cask