rampant

adj

1. Rearing on both hind legs with the forelegs extended.

   “The Vienna riding school displays splendid rampant movement.”

2. Rearing up, especially on its hind leg(s), with a foreleg raised and in profile.

   “‘I forget your coat of arms.’ ‘A human foot d’or, in a field azure; the foot crushes a serpent rampant whose fangs are imbedded in the heel.’”

   “little pieces of moustache on his upper lip, like a pair of minnows rampant”

   “The crest consists of a demi-lion rampant gules (red) holding between its paws a wheel argent similar to those included in the arms.”

3. Tilted, said of an arch with one side higher than the other, or a vault whose two abutments are located on an inclined plane.
4. Unrestrained or unchecked, usually in a negative manner.

   “Weeds are rampant in any neglected garden.”

   “Conditions were horrendous aboard most British naval vessels at the time. Scurvy and other diseases ran rampant, killing more seamen each year than all other causes combined, including combat.”

   “The craze for -ization — a word first employed by Charles Dickens in “Our Mutual Friend” — has been around for a very long time. The patron saint of rampant suffixization is Thomas Nashe, author of the 1593 pamphlet “Christ’s Tears Over Jerusalem.” His ebullient creations included myrmidonize, unmortalize, anthropophagize, retranquillize, cabbalize, palpabrize, superficialize and citizenize — not to mention collachrymate, assertionate and intercessionate.”

   “In contrast to the despair of his opposite number, it was a day of delight for new City boss Manuel Pellegrini as he watched the rampant Blues make a powerful statement about their Premier League ambitions.”

5. Rife, or occurring widely, frequently or menacingly.

   “There was rampant corruption in the city.”

adv

1. (informal, nonstandard)Rampantly.

   “Things seem to be running rampant around here lately.”