locomotive vs locomotive engine

locomotive and locomotive engine both are nouns.

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

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

locomotive and locomotive engine: a wheeled vehicle consisting of a self-propelled engine that is used to draw trains along railway tracks

Other synonyms of locomotive include engine, railway locomotive.

locomotive (noun)	locomotive engine (noun)
a wheeled vehicle consisting of a self-propelled engine that is used to draw trains along railway tracks	a wheeled vehicle consisting of a self-propelled engine that is used to draw trains along railway tracks

locomotive (adjective)	locomotive engine (adjective)
of or relating to locomotion