Paladin

from WordNet (r) 3.0 (2006)

paladin
    n 1: someone who fights for a cause [syn: {champion}, {fighter},
         {hero}, {paladin}]

from The Collaborative International Dictionary of English v.0.48

Paladin \Pal"a*din\, n. [F., fr.It. paladino, fr. L. palatinus
   an officer of the palace. See {Palatine}.]
   A knight-errant; a distinguished champion; as, the paladins
   of Charlemagne. --Sir W. Scott.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

34 Moby Thesaurus words for "paladin":
      Achilles, David, Hector, Roland, Samson, a man, advocate,
      apologist, brave, bulldog, champion, chutzpanik, decorated hero,
      defender, demigod, demigoddess, fighting cock, gallant, gamecock,
      good soldier, guard, hero, heroine, lion, man of courage,
      protector, stalwart, supporter, the brave, tiger, upholder,
      valiant, valiant knight, vindicator

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