definition of
crusade

[1] #1 crusade n. [campaign, cause, drive, movement, effort] 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. wn

[2] #2 crusade n. [Crusade] any of the more or less continuous military expeditions in the 11th to 13th centuries when Christian powers of Europe tried to recapture the Holy Land from the Muslims. wn

[3] #3 crusade v. [fight, press, campaign, push, agitate] 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 fav. wn

[4] #4 crusade v. go on a crusade; fight a holy war. wn