instrumentalist vs performer

instrumentalist and performer both are nouns.

Word	Noun	Adjective	Verb	Adverb
instrumentalist	Yes	No	No	No
performer	Yes	No	No	No

As nouns, performer is a hypernym of instrumentalist; that is, performer is a word with a broader meaning than instrumentalist:

instrumentalist: someone who plays a music as a profession
performer: an entertainer who performs a dramatic or musical work for an audience

Other hypernyms of instrumentalist include performing artist.

instrumentalist (noun)	performer (noun)
someone who plays a music as a profession	an entertainer who performs a dramatic or musical work for an audience