Flourishing or spreading unchecked. The rampant growth of weeds in the garden made it difficult to see the flowers.
Unrestrained or violent in action or performance. The rampant enthusiasm of the fans was evident as they cheered loudly for their team.
Standing on the hind legs with forepaws raised, as in heraldic depiction of an animal. The town’s crest displays a lion rampant clutching a sword.
Of an arch or vault, springing from a support at one level and rising to a higher level at the other end. The cathedral’s nave is spanned by a series of rampant arches.