A coonhound, colloquially a coon dog, is a type of scenthound, a member of the hound group. They are an American type of hunting dog developed for the hunting of raccoons and also for feral pigs, bobcats, cougars, and bears. There are six distinct breeds of coonhound.

Scent hounds are a type of hound that primarily hunts by scent rather than sight. These breeds are hunting dogs and are generally regarded as having some of the most sensitive noses among dogs. Scent hounds specialize in following scent or smells. Most of them tend to have long, drooping ears and large nasal cavities to enhance smell sensitivity. They need to have relatively high endurance to be able to keep track of scent over long distances and rough terrain. It is believed that they were first bred by the Celts by crossbreeding mastiff-type dogs with sighthounds. The first established scent hounds were St. Hubert Hounds bred by monks in Belgium during the Middle Ages.