Escapement

(-kāp'ment.) [Fr. échappement.] (Horol.) A mechanical contrivance for transmitting, in a modified way, the power of a clock or watch to the regulator, whether the latter is a balance or pendulum, for the purpose of restoring the motion lost at each vibration by friction, . Also, that part of a watch or timepiece by which the rotary motion of the wheels is converted into a vibratory one, as that of the balance of a watch, or the pendulum ofa clock. [s. 341]