hubby vs adult male

hubby and adult male both are nouns.

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

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

Other hypernyms of hubby include man, better half, married person, mate, partner, spouse.

hubby (noun)	adult male (noun)
a married man; a woman's partner in marriage	an adult person who is male (as opposed to a woman)