In mechanical watches and clocks, an escapement's a device which converts continuous rotational motion into an oscillating or back and forth motion. » The term's also used in fisheries science to refer to that portion of the spawning stock surviving fishing pressures over a spawning cycle. An escapement drives the timekeeping element, usually a pendulum or balance wheel, in a clock or watch. It's powered by a gear train which's typically turned by a coiled spring or weight. Without the escapeme… (More on Escapement)