Buck

1. The adult male of some animals, such as the deer, antelope, or rabbit. Shown is a male deer. Men try to shoot a buck during the deer season.
2. American money, one dollar, 100 cents. The book will cost you a buck.
3. A horse leaping upward arching its back, coming down with head low and forelegs stiff, forcefully kicking its hind legs upward in an attempt to dislodge the rider. The horse successfully bucked off the cowboy.