1. (n.) An enterprise undertaken with zeal and enthusiasm; as, a crusade against poverty\.

2. (n.) 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.

3. (n.) A Portuguese coin. See Crusado.

4. (v. i.) To engage in a crusade; to attack in a zealous or hot-headed manner.

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