Gelding
A gelding (/ˈɡɛldɪŋ/) is a castrated male horse or other equine, such as a pony, donkey or a mule. The term is also used with certain other animals and livestock, such as domesticated camels. The equivalent terms for castrated male cattle are steer or bullock, and wether for sheep and goats.
Castration renders the male animal calmer, better-behaved, less sexually aggressive, and more responsive to training efforts. This makes the animal generally more suitable as an everyday working animal, or as a pet in the case of companion animals. The gerund and participle "gelding" and the infinitive "to geld" refer to the castration procedure itself.