Canis Familiaris is the scientific name for the domestic DOG, commonly referred to as a DOG (3 letters). It is a species of the genus Canis, which also includes wolves, coyotes, and jackals. The term Canis Familiaris is used to distinguish the domesticated DOG from its wild relatives. Domesticated dogs have been kept as pets and working animals for thousands of years, and are now one of the most popular companion animals in the world.