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

See Examples For:

rotary engine

That’s prompted more companies to take a fresh look at old combustion tech, including the rotary engine, and figure out new ways for gas power and battery power to work together.

From The Wall Street Journal ● Apr. 26, 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 said that its prized rotary engine, introduced more than 50 years ago, was being adapted for electric vehicles.

From Seattle Times ● May 28, 2024

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The rack and sector patented at this time was soon superseded by the parallel-motion; and the last claim, the “steam-wheel” or rotary engine, although one was built of considerable size, was not introduced.

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