buckjumper

buck·jump

B0527300 (bŭk′jŭmp′)intr.v. buck·jumped, buck·jump·ing, buck·jumps 1. To buck, as a horse or mule does.2. To move in sudden jerks; lurch.
buck′jump·er n.

buckjumper

(ˈbʌkˌdʒʌmpə) n (Horse Training, Riding & Manège) Austral an untamed horse