dissident

adj. opposing, dissenting, disagreeing

n. dissenter, protester

A dissident, broadly defined, is a person who actively opposes an established opinion, policy, or structure. The term can be used to refer to a number of types of dissidents, including political, social, and militant dissidents.
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Noun
1. a person who dissents from some established policy
(synonym) dissenter, protester, objector, contestant
(hypernym) person, individual, someone, somebody, mortal, human, soul
(hyponym) conscientious objector, CO
Adjective
1. characterized by departure from accepted beliefs or standards
(synonym) heretical, heterodox
(similar) unorthodox
2. disagreeing, especially with a majority
(synonym) dissentient, dissenting(a)
(similar) negative

n. dissident, dissenter, objector, one who opposes or disagrees, protester

adj. dissident, disagreeing (Politics)

n. dissident, rebel, nonconformist