yachtsman vs adult female

yachtsman and adult female both are nouns.

Word	Noun	Adjective	Verb	Adverb
yachtsman	Yes	No	No	No
adult female	Yes	No	No	No

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

Other hypernyms of yachtsman include woman, yachtsperson.

yachtsman (noun)	adult female (noun)
a male person who owns or sails a yacht	an adult female person (as opposed to a man)