A donkey is a domesticated hoofed mammal belonging to the horse family and used as a work animal or for riding.
The offspring of a male donkey (jack) and a female horse (mare). Mules are sterile, which means they can't reproduce.
Domestication: The process by which humans alter the genetic traits of plants and animals to benefit themselves.
Equidae: The taxonomic family that includes horses, donkeys, zebras, and their extinct relatives.