rotary engine

American  

noun

1. an engine, as a turbine, in which the impelling fluid produces torque directly rather than by acting upon reciprocating parts.

2. a revolving radial engine.

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rotary engine British  

noun

1. an internal-combustion engine having radial cylinders that rotate about a fixed crankshaft

2. an engine, such as a turbine or wankel engine, in which power is transmitted directly to rotating components

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Etymology

Origin of rotary engine

First recorded in 1810–20

Example Sentences

During her life she secured more than 25 other permits, including for shoe-manufacturing equipment, improved window frames and sashes and a rotary engine.

From The Wall Street Journal • Apr. 9, 2026

Alongside Young’s RX-3 was Barbachan’s red ’72 Mazda RX-2, while Trujillo brought a vintage Mazda rotary engine pickup truck to the mix, as did Cabral with his ’74 sky-blue REPU.

From Los Angeles Times • Apr. 29, 2025

Mazda Motor Corp. is highlighting a sportscar concept that is a plug-in EV packed with its signature rotary engine.

From Seattle Times • Oct. 24, 2023

When he wasn’t looking for a job, Bruce worked on inventions—for 17 years on a design for a rotary engine that contained only three moving parts.

From Time • Sep. 8, 2016

The pump used with this engine is, as shown in the above illustration, somewhat similar to the rotary engine driving it.

From A History of the Growth of the Steam-Engine by Thurston, Robert H.