dress hat vs opera hat

dress hat and opera hat both are nouns.

Word	Noun	Adjective	Verb	Adverb
dress hat	Yes	No	No	No
opera hat	Yes	No	No	No

As nouns, dress hat and opera hat are synonyms defined as:

dress hat and opera hat: a man's hat with a tall crown; usually covered with silk or with beaver fur

Other synonyms of dress hat include beaver, high hat, silk hat, stovepipe, top hat, topper.

dress hat (noun)	opera hat (noun)
a man's hat with a tall crown; usually covered with silk or with beaver fur	a man's hat with a tall crown; usually covered with silk or with beaver fur