A helicopter twin-bladed main rotor, mounted on a pylon (Robinson R44)

A rotor is a rotating part of a machine, as in a motor, a pump or a helicopter. The part of the machine that does not rotate is called the stator.

A rotor may also be used to refer to an electric motor designed specifically to turn a receiving antenna to match the direction of the received signal.

da:Rotor de:Rotor fa:چرخانه ja:回転子