activist

from WordNet (r) 3.0 (2006)

activist
    adj 1: advocating or engaged in activism [syn: {activist},
           {activistic}]
    n 1: a militant reformer [syn: {militant}, {activist}]

from The Collaborative International Dictionary of English v.0.48

activist \activist\ n.
   1. one who is aggressively active on behalf of a cause.

   Syn: militant
        [WordNet 1.5] activist

from The Collaborative International Dictionary of English v.0.48

activist \activist\ activistic \activistic\adj.
   1. 1 advocating a cause or engaged in activism
      [WordNet 1.5]

from Moby Thesaurus II by Grady Ward, 1.0

22 Moby Thesaurus words for "activist":
      ball of fire, beaver, big-time operator, bustler, busy bee, doer,
      eager beaver, enthusiast, go-getter, human dynamo, hustler,
      live wire, man of action, man of deeds, militant, new broom,
      operator, political activist, powerhouse, take-charge guy,
      wheeler-dealer, winner

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