Extremist

n.

1.

A supporter of extreme doctrines or practice; one who holds extreme opinions.

Noun	1.	extremist - a person who holds extreme views
Adj.	1.	extremist - (used of opinions and actions) far beyond the norm; "extremist political views"; "radical opinions on education"; "an ultra conservative" Synonyms: radical, ultra

Bolshevik, Fabian, Jacobin, Wobbly, agitator, anarchist, anarchistic, anarcho-syndicalist, bigoted, brawler, extravagant, extreme, extreme left-winger, extremistic, fanatic, frondeur, haggard, inordinate, insubordinate, insurgent, insurrectionary, insurrectionist, insurrecto, irrational, left-wing extremist, lunatic fringe, malcontent, maverick, meliorist, mild radical, mildly radical, mutineer, nihilist, nihilistic, nonconformist, overenthusiastic, overreligious, overzealous, parlor Bolshevik, parlor pink, perfervid, pink, pinko, progressionist, progressist, progressive, progressivist, rabid, radical, rebel, red, reformer, reformist, revisionist, revolter, revolutional, revolutionary, revolutionist, rioter, sans-culotte, subversive, syndicalist, traitor, ultra, ultraconservative, ultraist, ultraistic, ultrazealous, unreasonable, utopian, utopist, wild-eyed, wild-looking, yippie, zealotic