jet engine

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An engine that develops thrust by ejecting a jet, especially a jet of gaseous combustion products.
• noun An engine that obtains the oxygen needed from the atmosphere, used especially to propel aircraft and distinguished from rocket engines having self-contained fuel-oxidizer systems.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun an engine that obtains thrust by taking in air at the front, using it to burn fuel, then ejecting the hot combustion products at the rear through a propulsive nozzle
• noun any engine propelled by expelling a high speed fluid jet (jet propulsion), such as a rocket, turbojet, turbofan, ramjet etc.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a gas turbine produces a stream of hot gas that propels a jet plane by reaction propulsion