high hat vs chapeau

high hat and chapeau both are nouns.

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

As nouns, chapeau is a hypernym of high hat; that is, chapeau is a word with a broader meaning than high hat:

high hat: a man's hat with a tall crown; usually covered with silk or with beaver fur
chapeau: headdress that protects the head from bad weather; has shaped crown and usually a brim

Other hypernyms of high hat include hat, lid, man's clothing.

high hat (noun)	chapeau (noun)
cymbals that are operated by a foot pedal	headdress that protects the head from bad weather; has shaped crown and usually a brim
a man's hat with a tall crown; usually covered with silk or with beaver fur