performer vs performing artist

performer and performing artist both are nouns.

Word	Noun	Adjective	Verb	Adverb
performer	Yes	No	No	No
performing artist	Yes	No	No	No

As nouns, performer and performing artist are synonyms defined as:

performer and performing artist: an entertainer who performs a dramatic or musical work for an audience

performer (noun)	performing artist (noun)
an entertainer who performs a dramatic or musical work for an audience	an entertainer who performs a dramatic or musical work for an audience