protester vs reformer

protester and reformer both are nouns.

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

As nouns, reformer is a hypernym of protester; that is, reformer is a word with a broader meaning than protester:

Other hypernyms of protester include crusader, meliorist, reformist, social reformer.

protester (noun)	reformer (noun)
someone who participates in a public display of group feeling	an apparatus that reforms the molecular structure of hydrocarbons to produce richer fuel
a person who dissents from some established policy	a disputant who advocates reform