escape wheel

English Thesaurus

1. gear that engages a rocking lever (noun.artifact)

hypernym	:	cogwheel, gear, gear wheel, geared wheel,
definition	:	a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion (noun.artifact)

part meronym	:	escapement,
definition	:	mechanical device that regulates movement (noun.artifact)