high hat vs silk hat

high hat and silk hat both are nouns.

Word	Noun	Adjective	Verb	Adverb
high hat	Yes	No	No	No
silk hat	Yes	No	No	No

As nouns, high hat and silk hat are synonyms defined as:

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

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

high hat (noun)	silk hat (noun)
cymbals that are operated by a foot pedal	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