turbojet engine vs turbojet

turbojet engine and turbojet both are nouns.

Word	Noun	Adjective	Verb	Adverb
turbojet engine	Yes	No	No	No
turbojet	Yes	No	No	No

As nouns, turbojet engine and turbojet are synonyms defined as:

turbojet engine and turbojet: a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust

Other synonyms of turbojet engine include fan-jet, fanjet, fanjet engine, turbofan, turbofan engine.

turbojet engine (noun)	turbojet (noun)
a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust	a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust
	an airplane propelled by a fanjet engine