General Definition: 1. The action of holding something firmly in your hand, pressing a button with your thumb, and then using force to move the object upwards towards you, such as operating various kinds of levers which act as locking devices. Without context and performed with the left hand, Auslan signers will assume you mean a hand-brake in a car. As a Noun: 1. A brake operated by hand, used to hold an already stationary vehicle. English = hand brake.