rotor

noun

ro·​tor ˈrō-tər 

1

a

: a part that revolves in a stationary part

a brake rotor

b

: the rotating member of an electrical machine

2

: an assembly of rotating blades that supplies lift or stability for a rotorcraft

Examples of rotor in a Sentence

Recent Examples on the Web

At the heart of the 41 mm timepiece lies the caliber JCHA01, with an in-house rotor that keeps time effortlessly and offers a 70-hour power reserve for weekend-proof autonomy. —Rachel Cormack, Robb Report, 31 Dec. 2025

The debris field, which consists of the main rotor and tail rotors, is about 100 yards long. —Sam Gillette, PEOPLE, 29 Dec. 2025

Instead, the next act of terror will begin with the buzzing sound of the drone rotors spinning at 5,000 rpm, audible only seconds before the swarm will reach its target. —Wired News, 27 Dec. 2025

Tektro hydraulic brakes, with four pistons and 180mm rotors front and rear, are standout components. —New Atlas, 18 Dec. 2025

Word History

Etymology

contraction of rotator

First Known Use

1892, in the meaning defined at sense 1a

Phrases Containing rotor

• tilt-rotor

Rhymes for rotor

• boater
• floater
• motor
• voter
• locomotor
• psychomotor
• servomotor
• vasomotor
• oculomotor
• sensorimotor
• premotor
• promoter

Kids Definition

rotor

noun

ro·​tor ˈrōt-ər 

1

: a part that rotates in a stationary part (as in an electrical machine)

2

: a complete system of rotating blades that support a helicopter in flight