contestant vs protester

contestant and protester both are nouns.

Word	Noun	Adjective	Verb	Adverb
contestant	Yes	No	No	No
protester	Yes	No	No	No

As nouns, contestant and protester are synonyms defined as:

contestant and protester: a person who dissents from some established policy

Other synonyms of contestant include dissenter, dissident, objector.

contestant (noun)	protester (noun)
a person who participates in competitions	someone who participates in a public display of group feeling
a person who dissents from some established policy	a person who dissents from some established policy