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 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

By 1914 forty-three different sizes and types of rotary engine were being constructed, and in 1913 five rotary type engines were entered for the series of aeroplane engine trials held in Germany.

From A History of Aeronautics by Vivian, Evelyn Charles