dancer vs showboy

dancer and showboy both are nouns.

Word	Noun	Adjective	Verb	Adverb
dancer	Yes	No	No	No
showboy	Yes	No	No	No

As nouns, showboy is a hyponym of dancer; that is, showboy is a word with a more specific, narrower meaning than dancer:

dancer (noun)	showboy (noun)
a performer who dances professionally	a man who dances in a chorus line
a person who participates in a social gathering arranged for dancing (as a ball)