rotor
/ˈrəʊtə
/noun
1A rotary part of a machine, in particular:As a message was typed into the machine, these rotors would spin around and calculate a letter to substitute for each letter of the message....
- This lessens the wear on brake drums, rotors and pads.
- Enigma allowed an operator to type in a message, then scramble it by means of three to five notched wheels, or rotors, which displayed different letters of the alphabet.
1.1A 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 aircraft featured two large rotors located in nacelles on the ends of its wings linked to an air-cooled Daimler Benz 600 engine in the fuselage....
- The aircraft would have launched standing upright like a rocket, but instead of using a blast of fire to take off the pilot would have simply adjusted the thrust and pitch of the rotors as with a helicopter.
- The sound of the helicopter's rumbling rotors became louder, as it flew by directly overhead us, and began hovering over the red smoke.
1.2The rotating assembly in a turbine.Should they malfunction or prove insufficient to slow the rotor in high winds, a large disk brake mounted on the generator shaft can smoothly bring the turbine to a halt....
- The higher-wattage plants, with their large-diameter, low-rotation-per-minute rotors, are designed to capture energy from low wind speeds.
- Take away the 2.2 birds killed by the rotors, and the balance for wind energy, + 1707.8 birds per turbine a year, is not bad.
1.3The armature of an electric motor.
1.4 (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.Motorists who failed to immobilise their cars, by taking away the rotor arm from the distributor, were liable to find their tyres deflated by the police....
- I immediately changed the oil, plugs, distributor cap, rotor arm, and a friendly independent specialist fixed the exhaust.
- After 20 minutes he decided the problem was with the rotor arm, and fashioned some wire underneath it to solve the problem.
1.5The rotating container in a centrifuge.One junior intelligence analyst thought that although they weren't at all like modern American centrifuge rotors, they might be usable in what are known as a Zippe centrifuge....
- The Department of Energy rejected the claim that the country was importing aluminum tubes to produce centrifuge rotors for enriching uranium.
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.