Bucking
Bucking is the term used for when a horse kicks out with both hind legs at the same time. Bucking can often unseat a rider, especially an inexperienced one. It can be dangerous to ride a horse that bucks, therefore it is useful to know why a horse bucks and how to deal with it.
Bucking can be a normal behaviour in a herd situation, but could be a sign of pain in a horse under saddle