WordNet (r) 3.0 (2006):

revisionist
    n 1: a Communist who tries to rewrite Marxism to justify a
         retreat from the revolutionary position

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "revisionist":
   Bolshevik, Bolshevist, Castroite, Communist, Communist sympathizer,
   Fabian, Leninist, Maoist, Marxist, Marxist-Leninist, Red,
   Stalinist, Titoist, Trotskyist, Trotskyite, avowed Communist,
   bolshie, commie, communistic, corrective, emendatory, extremist,
   fellow traveler, gradualistic, meliorist, melioristic,
   progressionist, progressist, progressive, progressivist, radical,
   reformational, reformative, reformatory, reformer, reformist,
   reformistic, revisional, revisory, revolutionary, utopian,
   utopist