enemy vs military unit

enemy and military unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
enemy	Yes	No	No	No
military unit	Yes	No	No	No

As nouns, military unit is a hypernym of enemy; that is, military unit is a word with a broader meaning than enemy:

Other hypernyms of enemy include force, military force, military group.

enemy (noun)	military unit (noun)
an opposing military force	a unit that is part of some military service
any hostile group of people
an armed adversary (especially a member of an opposing military force)
a personal enemy