heat engine

American  

noun

Thermodynamics.

1. a mechanical device designed to transform part of the heat entering it into work.

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heat engine British  

noun

1. an engine that converts heat energy into mechanical energy

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Etymology

Origin of heat engine

First recorded in 1890–95

Example Sentences

Depending on conditions, it can function as a refrigerator, act as a heat engine, or amplify thermal transport.

From Science Daily • Jan. 29, 2026

Nearly two centuries ago, French physicist Sadi Carnot established the theoretical maximum efficiency that any heat engine can achieve.

From Science Daily • Jan. 22, 2026

“You can think of a hurricane as a heat engine where the ocean is the fuel … so giving it warmer water is basically like higher-octane fuel,” Hazelton said.

From Seattle Times • Sep. 4, 2023

The actual reservoir temperatures of a heat engine are usually related to the type of heat source and the temperature of the environment into which heat transfer occurs.

From Textbooks • Aug. 12, 2015

These were the two great improvements which converted the first real steam engine into an economical form of heat engine and essentially finished the work so grandly begun by Newcomen and Calley.

From Scientific American Supplement, No. 803, May 23, 1891 by Various