A bootee is a short soft sock or bootlike garment used for warmth or protection. Bootees for babies are usually thick and knitted, to keep the baby's feet warm. There are dog booties

Dog booties

Dog booties, commonly called "booties", are rubber, fabric, or plastic coverings for dogs' paws, used to protect the animal from cold weather, rough terrain, or injury. They are analogous to human shoes and are most common in sled dog races. Many races require booties as a basic element of dog care...

 used by dogs such as sledge dogs in very cold Arctic

Arctic

The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...

 conditions (see Iditarod Trail Sled Dog Race) to protect the animal from the cold.

Disposable socks, such as those worn for hygiene by surgical teams, are also called bootees.