a hub with a number of radiating aerofoils that is rotated in an approximately horizontal plane to provide the lift for a rotary wing aircraft.
the rotating assembly in a turbine.
the armature of an electric motor.
(also rotor arm) the rotating part of the distributor of an internal-combustion engine which successively makes and breaks electrical contacts so that each spark plug fires in turn.
the rotating container in a centrifuge.
2 Meteorology a large eddy in which the air circulates about a horizontal axis, especially in the lee of a mountain: [as modifier]:a rotor cloud
Origin:
early 20th century: formed irregularly from rotator
