rocket engine

American  

noun

1. a reaction engine that produces a thrust due to an exhaust consisting entirely of material, as oxidizer, fuel, and inert matter, that has been carried with the engine in the vehicle it propels, none of the propellant being derived from the medium through which the vehicle moves.

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rocket engine British  

noun

1. Also called: rocket motor.  a reaction engine in which a fuel and oxidizer are burnt in a combustion chamber, the products of combustion expanding through a nozzle and producing thrust

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rocket engine Scientific  

1. An engine used to produce a jet of hot gases to propel a rocket. The jet is produced by combustion of a fuel with other chemicals stored in the rocket. Since they do not rely on the oxygen in the atmosphere for combustion, rocket engines can operate in space.

2. Compare turbojet

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Etymology

Origin of rocket engine

First recorded in 1930–35

Example Sentences

North Korean leader Kim Jong Un oversaw the ground test of an upgraded rocket engine, state media reported on Sunday, marking another key step in its weapons programme.

From Barron's • Mar. 29, 2026

But the company failed to land New Glenn's main rocket engine, or booster, onto a platform in the Atlantic Ocean.

From BBC • Jan. 16, 2025

During a test of a Harpoon anti-ship missile, its booster — the rocket engine that launches the missile — was “activated” but not ignited, and then it could not be deactivated, the Danish military said.

From New York Times • Apr. 4, 2024

The Talon, powered by a liquid-fuel rocket engine, ended its flight by descending into the ocean as planned.

From Seattle Times • Mar. 9, 2024

We fired Columbia’s rocket engine shortly after we swung around behind the moon’s left edge, out of touch with the earth for the first time in three days.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins