[1] : The Collaborative International Dictionary of English v.0.48

crusade \crusade"\ kr?-s?d", n. f. croisade, fr. pr.
   crozada, or sp cruzada, or it. crociata, from a verb
   signifying to take the cross, mark one's self with a cross,
   fr. l. crux cross; or possibly taken into english directly
   fr. pr. cf. croisade, crosado, and see cross.
   1. any one of the military expeditions undertaken by
      christian powers, in the 11th, 12th, and 13th centuries,
      for the recovery of the holy land from the mohammedans.
      1913 webster

   2. any enterprise undertaken with zeal and enthusiasm; as, a
      crusade against intemperance.
      1913 webster

   3. a portuguese coin. see crusado.
      1913 webster
see also:
croisade crosado cross crusado 

[2] : The Collaborative International Dictionary of English v.0.48

crusade \crusade"\, v. i. imp.  p. p. crusaded; p. pr. 
   vb. n. crusading.
   to engage in a crusade; to attack in a zealous or hot-headed
   manner. "cease crusading against sense." --m. green.
   1913 webster
see also:
crusaded crusading 

[3] : WordNet (r) 2.0

crusade
     n 1: a series of actions advancing a principle or tending toward
          a particular end; "he supported populist campaigns";
          "they worked in the cause of world peace"; "the team was
          ready for a drive toward the pennant"; "the movement to
          end slavery"; "contributed to the war effort" syn: campaign,
           cause, drive, movement, effort
     2: any of the more or less continuous military expeditions in
        the 11-13th centuries when christian powers of europe
        tried to recapture the holy land from the muslims
     v 1: exert oneself continuously, vigorously, or obtrusively to
          gain an end or engage in a crusade for a certain cause
          or person; be an advocate for; "the liberal party pushed
          for reforms"; "she is crusading for women's rights";
          "the dean is pushing for his favorite candidate" syn: fight,
           press, campaign, push, agitate
     2: go on a crusade; fight a holy war
see also:
campaign cause drive movement effort fight 
press push agitate 

[4] : Moby Thesaurus II by Grady Ward, 1.0

22 moby thesaurus words for "crusade":
   activity, battle, campaign, cause, commitment, drive, expedition,
   faith, fight, great cause, holy war, interest, issue, jehad, jihad,
   lifework, lobby, mass movement, movement, principle,
   reason for being, war

Crusade >> C Words
Crusade, definition of term: Crusade
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