showgirl vs professional dancer

showgirl and professional dancer both are nouns.

Word	Noun	Adjective	Verb	Adverb
showgirl	Yes	No	No	No
professional dancer	Yes	No	No	No

As nouns, professional dancer is a hypernym of showgirl; that is, professional dancer is a word with a broader meaning than showgirl:

Other hypernyms of showgirl include dancer, terpsichorean, adult female, woman.

showgirl (noun)	professional dancer (noun)
a woman who dances in a chorus line	a performer who dances professionally