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noun

rotor

ROH-tuh
noun
1
The rotating part of a motor, generator, or similar machine.
"The rotor spins inside the motor's stationary casing."
2
The spinning blade assembly of a helicopter.
"The helicopter's rotor kicked up dust as it landed."
3
The metal disc a car's brake pads clamp onto in a disc brake.
"The mechanic replaced the worn brake rotors."

How to Use Rotor

Learner’s notes

In plain EnglishA spinning part of a machine — in everyday use, most often either a helicopter's blades or a car's brake disc.

Common pairings
rotor blades brake rotor main rotor

Word Forms

rotors plural

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Fill the Gap

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The _____ spins inside the motor's stationary casing.

Etymology

A shortened form of "rotator," first used in mathematics before being adopted for spinning machine parts.

Rhymes for rotor

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Definitions: FreeDict original editorial