coxcomb vs beau

coxcomb and beau both are nouns.

Word	Noun	Adjective	Verb	Adverb
coxcomb	Yes	No	No	No
beau	Yes	No	No	No

As nouns, beau is a hypernym of coxcomb; that is, beau is a word with a broader meaning than coxcomb:

coxcomb: a conceited dandy who is overly impressed by his own accomplishments
beau: a man who is much concerned with his dress and appearance

Other hypernyms of coxcomb include clotheshorse, dandy, dude, fashion plate, fop, gallant, sheik, swell.

coxcomb (noun)	beau (noun)
the fleshy red crest on the head of the domestic fowl and other gallinaceous birds	a man who is the lover of a man or woman
a cap worn by court jesters; adorned with a strip of red	a man who is much concerned with his dress and appearance
a conceited dandy who is overly impressed by his own accomplishments