ma'am vs adult female

ma'am and adult female both are nouns.

Word	Noun	Adjective	Verb	Adverb
ma'am	Yes	No	No	No
adult female	Yes	No	No	No

As nouns, adult female is a hypernym of ma'am; that is, adult female is a word with a broader meaning than ma'am:

Other hypernyms of ma'am include woman.

ma'am (noun)	adult female (noun)
a woman of refinement	an adult female person (as opposed to a man)