rotor

American  

[roh-ter] / ˈroʊ tər /

noun

1. Electricity. a rotating member of a machine.

2. Aeronautics. a system of rotating airfoils, as the horizontal ones of a helicopter or of the compressor of a jet engine.

3. any of a number of tall, cylindrical devices mounted on a special ship rotor ship and rotated in such a way that the Magnus effect of wind impinging on the cylinders is used to drive and maneuver the vessel.

4. (in a self-winding watch) a weight eccentrically mounted on an arbor for keeping the mainspring wound.

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rotor British  

/ ˈrəʊtə /

noun

1. the rotating member of a machine or device, esp the armature of a motor or generator or the rotating assembly of a turbine Compare stator

2. a device having blades radiating from a central hub that is rotated to produce thrust to lift and propel a helicopter

3. the revolving arm of the distributor of an internal-combustion engine

4. a violent rolling wave of air occurring in the lee of a mountain or hill, in which the air rotates about a horizontal axis

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Etymology

Origin of rotor

First recorded in 1873; short for rotator

Example Sentences

As the light show unfolded, the lantern's blindingly bright facades concealed a flurry of activity behind, as teams of people turned large metal barrels called rotors by hand to produce a kaleidoscopic effect.

From Barron's

On 11 January, the crew said they were woken by the sound of helicopter rotors overhead and a US Navy ship pulling alongside.

From BBC

As the wings begin to generate lift, the rotors’ pace slackens.

From The Wall Street Journal

He said that the lighter materials, combined with more effective motors to drive the rotors, mean it's much more effective than a century ago.

From BBC

A tweet about Tuesday’s announcement included a video showing a spinning wheel with a Tesla logo that could have been the rotor of a Tesla eVTOL, or quadcopter drone.

From Barron's