rotor

noun

ro·​tor ˈrō-tər How to pronounce rotor (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The pilot, who holds an Airline Transport Pilot certificate and multiple commercial ratings, attempted an emergency maneuver with the rotors when the engine cut out, but that was unsuccessful and resulted in a hard landing, according to authorities. Shannon Tyler, Idaho Statesman, 22 Oct. 2025 Effective stopping power is provided by Tektro HD-M275 hydraulic disc brakes with 160-mm rotors. New Atlas, 22 Oct. 2025 Equipped with advanced turboshaft engines, high-efficiency rotor systems, and anti-icing technology, the military variants of the Z-20 are built for demanding operational conditions. Bojan Stojkovski, Interesting Engineering, 19 Oct. 2025 Some videos of the crash circulating on social media appear to show the tail rotor slowing down and coming to a stop as the helicopter starts to spin to the right. Nathaniel Percy, Oc Register, 16 Oct. 2025 See All Example Sentences for rotor

Word History

Etymology

contraction of rotator

First Known Use

1892, in the meaning defined at sense 1a

Time Traveler
The first known use of rotor was in 1892

Browse Nearby Words

Cite this Entry

“Rotor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rotor. Accessed 30 Oct. 2025.

Kids Definition

rotor

noun
ro·​tor ˈrōt-ər How to pronounce rotor (audio)
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

More from Merriam-Webster on rotor

Last Updated: - Updated example sentences
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