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.

---

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

---

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.

From The Wall Street Journal ● Apr. 24, 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 Rotary, of New York, was a new steamer for freighting purposes, with a rotary engine and common propeller.

From History of Steam on the Erie Canal by Anonymous