cocked hat vs bicorne

cocked hat and bicorne both are nouns.

Word	Noun	Adjective	Verb	Adverb
cocked hat	Yes	No	No	No
bicorne	Yes	No	No	No

As nouns, bicorne is a hyponym of cocked hat; that is, bicorne is a word with a more specific, narrower meaning than cocked hat:

cocked hat: hat with opposing brims turned up and caught together to form points
bicorne: a cocked hat with the brim turned up to form two points

Other hyponyms of cocked hat include bicorn, tricorn, tricorne.

cocked hat (noun)	bicorne (noun)
hat with opposing brims turned up and caught together to form points	a cocked hat with the brim turned up to form two points