prince vs adult male

prince and adult male both are nouns.

Word	Noun	Adjective	Verb	Adverb
prince	Yes	No	No	No
adult male	Yes	No	No	No

As nouns, adult male is a hypernym of prince; that is, adult male is a word with a broader meaning than prince:

prince: a male member of a royal family other than the sovereign (especially the son of a sovereign)
adult male: an adult person who is male (as opposed to a woman)

Other hypernyms of prince include aristocrat, blue blood, patrician, man.

prince (noun)	adult male (noun)
a male member of a royal family other than the sovereign (especially the son of a sovereign)	an adult person who is male (as opposed to a woman)