a mechanism in a clock or watch that alternately checks and releases the train by a fixed amount and transmits a periodic impulse from the spring or weight to the balance wheel or pendulum.
a mechanism in a typewriter that shifts the carriage a small fixed amount to the left after a key is pressed and released.
the part of the mechanism in a piano that enables the hammer to fall back as soon as it has struck the string.
Origin:
late 18th century: from French échappement, from échapper 'to escape'
