adj. 1 (placed after noun) Heraldry (of an animal) standing on its left hind foot with its forepaws in the air (lion rampant). 2 unchecked, flourishing excessively (rampant violence). 3 violent or extravagant in action or opinion (rampant theorists). 4 rank, luxuriant. rampancy n. rampantly adv.
[ ME f. OF, part. of ramper: see RAMP(1) ]