Available Definitions:
1) 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.
2) n. - Any enterprise undertaken with zeal and enthusiasm; as, a crusade against intemperance.
3) n. - A Portuguese coin. See Crusado .
4) v. i. - To engage in a crusade; to attack in a zealous or hot-headed manner.