A mixed-breed dog is a cross between dogs of two or more different breeds.
Mixed-breed dogs can vary in the complexity of their heritage – from the most simple first generation cross breed mix of two pedigree breeds (for example, the Cockapoo, which is usually the offspring of a Cocker Spaniel
and a Miniature Poodle
) to outbred dogs that live in freely interbreeding populations in the wild.
Outbred or wild dogs have no recent ancestry from pedigree dog populations, and can be considered to be extremely mixed-breed dogs. In many outbred dogs, all eight great-grandparents were also mixed breed dogs.
Mixed-breed dogs vary greatly in size, shape, and color, and consequently, are often difficult to classify physically.