thespian vs performer

thespian and performer both are nouns.

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

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

thespian: a theatrical performer
performer: an entertainer who performs a dramatic or musical work for an audience

Other hypernyms of thespian include performing artist.

thespian (noun)	performer (noun)
a theatrical performer	an entertainer who performs a dramatic or musical work for an audience

thespian (adjective)	performer (adjective)
of or relating to drama