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

An explosion separated the Bell’s tail boom, main rotor, mast and transmission and sent the fuselage crashing into the ground. —Alexandra Skores, CNN Money, 12 Sep. 2025

Renaud Tixier’s movement is a highly innovative micro-rotor movement that features an inertia wheel within the micro-rotor and a ‘dancer’ spring, orchestrated to optimize winding by harvesting even the smallest motion. —Thor Svaboe, Robb Report, 9 Sep. 2025

For the watchmaker, that decade saw the development of the El Primero caliber, the first automatic high-frequency chronograph movement, one that came with a full-rotor design giving it 1/10th-of-a-second precision. —Lily Templeton, Footwear News, 4 Sep. 2025

Four silicone base pads extrude glue which sets rapidly, so the drone remains stuck in place when the rotors are turned off. —David Hambling, Forbes.com, 3 Sep. 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