rotor

noun ro·tor \ ˈrō-tər \

|Updated on: 9 Jul 2018

Definition of rotor

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

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Recent Examples of rotor from the Web

The rotor roared above the Sonoran desert, kicking up dust and wind.

— alex devoid, azcentral, "Drought raises demand for water deliveries to wildlife, but it's a short-term fix," 27 June 2018
Theft, Aurora Road: At 1:45 a.m. May 4, a representative of Liberty Ford, 32811 Aurora Road, reported that someone had stolen a container filled with brake rotors between May 4-7.

— jeff piorkowski/special to cleveland.com, cleveland.com, "Man arrested after knives, methamphetamine found in his car: Solon police blotter," 11 May 2018
The aircraft, known as Cora, has a wingspan of 36 feet with a dozen rotors all powered by batteries.

— andrew ross sorkin, New York Times, "Larry Page’s Flying Taxis, Now Exiting Stealth Mode," 12 Mar. 2018
Protocol requires each helicopter to be one rotor disc apart, or about 40 feet.

— popular mechanics editors, Popular Mechanics, "The Secrets of Summer 2018's Greatest Movie Stunts and Effects," 20 June 2018
The UTA Research Institution is working with a $1 million agreement with NASA developing state-of-the-art computational methodologies to predict the strength and life of rotor blade assemblies.

— richard greene, star-telegram, "UT Arlington has bragging rights," 21 May 2018
One is that the propellers and rotors used to lift conventional aircraft are not effective at small scales, where the viscosity of air is a problem.

— The Economist, "The world’s lightest wireless flying machine lifts off," 15 May 2018
The station is used heavily by residents of Southwest Center City traveling to the airport, yet SEPTA decided to install ceiling-high rotor gates.

— inga saffron, Philly.com, "There's no getting around the clumsy design of SEPTA's new fare gates," 9 May 2018
The frenzied exchanges – frequently taking place over the roar of Marine One's rotor – often produce news.

— jill colvin, The Christian Science Monitor, "White House avoids press conferences in favor of informal exchanges," 1 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rotor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of rotor

contraction of rotator

NEW! Time Traveler

First Known Use: 1892

in the meaning defined at sense 1a

See Words from the same year

ROTOR Defined for English Language Learners

rotor

noun

Definition of rotor for English Language Learners

: a part of a machine that turns around a central point

ROTOR Defined for Kids

rotor

noun ro·tor \ ˈrō-tər \

Definition of rotor for Students

1 : the part of an electrical machine that turns

2 : a system of spinning horizontal blades that support a helicopter in the air

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See words that rhyme with rotor Spanish Central: Translation of rotor Nglish: Translation of rotor for Spanish speakers

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rotor

Definition of rotor

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ROTOR Defined for English Language Learners

rotor

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rotor

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rotor

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