artillery vs artillery unit

artillery and artillery unit both are nouns.

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

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

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