cavalier hat vs chapeau

cavalier hat and chapeau both are nouns.

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

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

cavalier hat: a soft felt hat with a wide flexible brim
chapeau: headdress that protects the head from bad weather; has shaped crown and usually a brim

Other hypernyms of cavalier hat include hat, lid.

cavalier hat (noun)	chapeau (noun)
a soft felt hat with a wide flexible brim	headdress that protects the head from bad weather; has shaped crown and usually a brim