A male fox is called a reynard, the female is called a vixen, and the baby is called a kit. A group of foxes is called a skulk or a leash. The fur of the Arctic fox is white during the winter and gray-brown in the summer. This is effective camouflage for the fox. The long, bushy tail, sometimes called a sweep, helps the fox change direction quickly and keeps the fox's feet and nose warm when it curls up to sleep.
Foxes have sharp, curved claws, sharp teeth, and thick, insulating fur.
The relatively small size of the Arctic fox's ears mimimizes heat loss. This fox sometimes follows a polar bear in order to feed on the remains of its kills.