What is the meaning of Escapement?

The linkage in a (watch) that gives impulses to the timekeeping element and periodically releases the gear train to move forward, advancing the clock's hands.

A mechanism found in devices such as a typewriter or printer which controls lateral motion of the carriage.

An escape or a means of escape.

The number of fish that escape commercial fishing operations and travel upstream to spawn.

Source: wiktionary.org