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Webster 1913 Edition

(-hwēl)

Noun.

(Mach.)

Any wheel worked by hand; esp., one the rim of which serves as the handle by which a valve, car brake, or other part is adjusted.

handwheel ‎(plural handwheels)

(mechanics) Any wheel worked by hand, whether used to allow leverage, as of a valve or a handbrake, or to allow fine adjustment, as of a setscrew.