ROTC vs corps

ROTC and corps both are nouns.

Word	Noun	Adjective	Verb	Adverb
ROTC	Yes	No	No	No
corps	Yes	No	No	No

As nouns, corps is a hypernym of ROTC; that is, corps is a word with a broader meaning than ROTC:

ROTC: a training program to prepare college students to be commissioned officers
corps: an army unit usually consisting of two or more divisions and their support

Other hypernyms of ROTC include army corps.

ROTC (noun)	corps (noun)
a training program to prepare college students to be commissioned officers	an army unit usually consisting of two or more divisions and their support
	a body of people associated together