Search Result for "power brake":
Wordnet 3.0

NOUN (1)

1. a brake on an automobile that magnifies a small force applied to the brake pedal into a proportionately larger force applied to slow or stop the vehicle; 



WordNet (r) 3.0 (2006):

power brake
    n 1: a brake on an automobile that magnifies a small force
         applied to the brake pedal into a proportionately larger
         force applied to slow or stop the vehicle