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.

---

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

---

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

---

Etymology

Origin of rocket engine

First recorded in 1930–35

Example Sentences

"This large rocket engine will slow down the ISS, and enable it to have a precise re-entry over the Pacific Ocean, far from land, people or any other potential hazards," Horack explained.

From Barron's • Feb. 5, 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

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

An accurate replica of the rocket engine will be launched and actors will depict members of Butler’s fictional Earthseed community from her “Parable” novels.

From Los Angeles Times • Oct. 31, 2023

We ignited Columbia’s rocket engine once, for just three seconds, to adjust our course slightly.

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