dancer vs raver

dancer and raver both are nouns.

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

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

dancer: a person who participates in a social gathering arranged for dancing (as a ball)
raver: a participant in a rave dancing party

Other hyponyms of dancer include clog dancer, dancing partner, folk dancer, waltzer.

dancer (noun)	raver (noun)
a performer who dances professionally	someone who rants and raves; speaks in a violent or loud manner
a person who participates in a social gathering arranged for dancing (as a ball)	a participant in a rave dancing party