adult male vs male

adult male and male both are nouns.

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

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

Other hypernyms of adult male include adult, grownup, male person.

adult male (noun)	male (noun)
an adult person who is male (as opposed to a woman)	an animal that produces gametes (spermatozoa) that can fertilize female gametes (ova)
	a person who belongs to the sex that cannot have babies

adult male (adjective)	male (adjective)
	being the sex (of plant or animal) that produces gametes (spermatozoa) that perform the fertilizing function in generation
	for or pertaining to or composed of men or boys
	characteristic of a man