escapement

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A mechanism consisting in general of an escape wheel and an anchor, used especially in timepieces to control movement of the wheel and to provide periodic energy impulses to a pendulum or balance.
2. n. A mechanism, as in a typewriter, that controls the lateral movement of the carriage.
3. n. An escape.
4. n. A means or way of escape.

Century Dictionary and Cyclopedia

1. n. The act of escaping; escape.
2. n. The general contrivance in a timepiece by which the pressure of the wheels (which move always in one direction) and the vibratory motion of the pendulum or balancewheel are accommodated the one to the other. By this contrivance the wheelwork is made to communicate an impulse to the regulating power (which in a clock is the pendulum and in a watch the balance-wheel), so as to restore to it the small portion of force which it loses in every vibration, in consequence of friction and the resistance of the air. The leading requisite of a good escapement is that the impulse communicated to the pendulum be invariable, notwithstanding any irregularity or foulness in the train of wheels. Various kinds of escapements have been contrived: such as the crown- or verge-escapement, used in common watches, and the anchor- or crutch-escapement, in common clocks—both also termed recoiling escapements; the deadbeat escapement and the gravity- or remontoir-escapement, used in the finer kind of clocks; the horizontal escapement or cylinder-escapement, the detached escapement, the lever-escapement, the duplex escapement, the pinwheel escapement, all used in the finer classes of watches; and the half-dead escapement, in which there is a slight recoil. In the horizontal escapement the teeth of a horizontal wheel act upon a hollow cylinder on the axis of the balance, to give the impulse.
3. n. In pianoforte-making, that part of the action which provides that the hammer, after striking the string, shall instantly recoil, whether or not the key is released. The escapement is called double when the mechanism admits of giving a second blow without fully releasing the key.

Wiktionary

1. n. The contrivance in a timepiece (winding wrist watch) which connects the train of wheel work with the pendulum or balance, giving to the latter the impulse by which it is kept in vibration; -- so called because it allows a tooth to escape from a pallet at each vibration.
2. n. a mechanism found in devices such as a typewriter or printer which controls lateral motion of the carriage
3. n. an escape or means of escape

GNU Webster's 1913

1. n. rare The act of escaping; escape.
2. n. rare Way of escape; vent.
3. n. The contrivance in a timepiece which connects the train of wheel work with the pendulum or balance, giving to the latter the impulse by which it is kept in vibration; -- so called because it allows a tooth to escape from a pallet at each vibration.

WordNet 3.0

1. n. mechanical device that regulates movement