Rampant \Ramp"ant\, a. [F., p. pr. of ramper to creep. See Ramp, v.]

1. Ramping; leaping; springing; rearing upon the hind legs; hence, raging; furious.

The fierce lion in his kind Which goeth rampant after his prey. --Gower.

[The] lion . . . rampant shakes his brinded mane. --Milton.

2. Ascending; climbing; rank in growth; exuberant.

The rampant stalk is of unusual altitude. --I. Taylor.

3. (Her.) Rising with fore paws in the air as if attacking; -- said of a beast of prey, especially a lion. The right fore leg and right hind leg should be raised higher than the left.

Rampant arch.
   (a) An arch which has one abutment higher than the other.
   (b) Same as Rampant vault, below.

Rampant gardant (Her.), rampant, but with the face turned to the front.

Rampant regardant, rampant, but looking backward.

Rampant vault (Arch.), a continuous wagon vault, or cradle vault, whose two abutments are located on an inclined planed plane, such as the vault supporting a stairway, or forming the ceiling of a stairway.

Source: Webster's Revised Unabridged Dictionary (1913)