woman's hat vs turban

woman's hat and turban both are nouns.

Word	Noun	Adjective	Verb	Adverb
woman's hat	Yes	No	No	No
turban	Yes	No	No	No

As nouns, turban is a hyponym of woman's hat; that is, turban is a word with a more specific, narrower meaning than woman's hat:

Other hyponyms of woman's hat include church hat, cloche, picture hat, pillbox, toque.

woman's hat (noun)	turban (noun)
hats for women; the wares sold by a milliner	a traditional Muslim headdress consisting of a long scarf wrapped around the head
	a small round woman's hat