The ferret (Mustela furo) is a small, domesticated species belonging to the family Mustelidae. The ferret is most likely a domesticated form of the wild European polecat (Mustela putorius), evidenced by their interfertility.
Physically, ferrets resemble other mustelids because of their long, slender bodies. Including their tail, the average length of a ferret is about ; they weigh between ; and their fur can be black, brown, white, or a mixture of those colours. The species is sexually dimorphic, with males being considerably larger than females.
Ferrets may have been domesticated since ancient times, but there is widespread disagreement because of the sparseness of written accounts and the inconsistency of those which survive. Contemporary scholarship agrees that ferrets were bred for sport, hunting rabbits in a practice known as rabbiting. In North America, the ferret has become an increasingly prominent choice of household pet, with over five million in the United States alone. T