fanjet vs jet engine

fanjet and jet engine both are nouns.

Word	Noun	Adjective	Verb	Adverb
fanjet	Yes	No	No	No
jet engine	Yes	No	No	No

As nouns, jet engine is a hypernym of fanjet; that is, jet engine is a word with a broader meaning than fanjet:

fanjet: a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust
jet engine: a gas turbine produces a stream of hot gas that propels a jet plane by reaction propulsion

fanjet (noun)	jet engine (noun)
a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust	a gas turbine produces a stream of hot gas that propels a jet plane by reaction propulsion
an airplane propelled by a fanjet engine