monologist vs performer

monologist and performer both are nouns.

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

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

monologist: an entertainer who performs alone
performer: an entertainer who performs a dramatic or musical work for an audience

Other hypernyms of monologist include performing artist.

monologist (noun)	performer (noun)
an entertainer who performs alone	an entertainer who performs a dramatic or musical work for an audience