brake disk

English Thesaurus

1. a disk or plate that is fixed to the wheel; pressure is applied to it by the brake pads (noun.artifact)

hypernym	:	disc, disk,
definition	:	a flat circular plate (noun.artifact)

part meronym	:	disc brake, disk brake,
definition	:	hydraulic brake in which friction is applied to both sides of a spinning disk by the brake pads (noun.artifact)