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

How efficient, then, can a heat engine be?

From Textbooks • Aug. 12, 2015

Thus in his theory as much heat was given up by a heat engine to the body at the lower temperature as was received by it from the source.

From Lord Kelvin An account of his scientific life and work by Gray, Andrew