A leap like that of a buck, esp. a jump from the ground made by an untamed or vicious horse, with the feet drawn together and the back arched, to…

An act of bucking; the power to buck. Cf. buck-jump, n.

U.S. In a rodeo: a manner of bucking in which the horse or steer twists its body into a crescent shape at the top of its jump. Cf. sunfish, v.