noun A vertical cylindrical machine that revolves on a spindle, typically surmounted by a drumhead with sockets for levers for turning it; used to apply force to cables, ropes, etc.
to pawl the capstan
noun A rotating spindle used to move recording tape through the mechanism of a tape recorder.
noun a screw on the rising side of a piano key, which serves the function of lifting the wippen when the key is depressed