Englishwoman vs adult female

Englishwoman and adult female both are nouns.

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

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

Other hypernyms of Englishwoman include English person, woman.

Englishwoman (noun)	adult female (noun)
a woman who is a native or inhabitant of England	an adult female person (as opposed to a man)