seamstress vs adult female

seamstress and adult female both are nouns.

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

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

Other hypernyms of seamstress include dressmaker, garment-worker, garment worker, garmentmaker, woman.

seamstress (noun)	adult female (noun)
a woman who makes or mends dresses	an adult female person (as opposed to a man)