artillery unit vs artillery

artillery unit and artillery both are nouns.

Word	Noun	Adjective	Verb	Adverb
artillery unit	Yes	No	No	No
artillery	Yes	No	No	No

As nouns, artillery unit and artillery are synonyms defined as:

artillery unit (noun)	artillery (noun)
an army unit that uses big guns	large but transportable armament
	a means of persuading or arguing
	an army unit that uses big guns