The word fox comes from Old English, which derived from Proto-Germanic *fuhsaz. This in turn derives from Proto-Indo-European*puḱ- ‘thick-haired; tail. Male foxes are known as dogs, tods or reynards, females as vixens, and young as cubs, pups, or kits. A group of foxes is usually called a skulk, leash, or earth.

Fox species differ in fur color, length, and density. Their lifespan also depends on the species, and the average life expectancy is 1 to 3 years in the wild. Some individual can live up to 10 years. Foxes belong to the canidae family, but, unlike other canids, they are not always social. Some foxes prefer to be solitary, but most of them live in small families.

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