1.NounA 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; to rig the capstan; to surge the capstan"
2.NounA rotating spindle used to move recording tape through the mechanism of a tape recorder.
3.Nouna screw on the rising side of a piano key, which serves the function of lifting the wippen when the key is depressed