Glossary
Undercoat
The soft, short, dense layer of fur beneath the longer outer guard hairs of a double-coated dog, which provides insulation and is shed in large amounts.
Also called: under coat, woolly undercoat, down coat, undercoat rake
The undercoat is the fine, woolly or downy fur that grows close to the skin beneath the outer guard hairs. It traps air and works as insulation, keeping a dog warmer in cold weather and shielding it from heat. Breeds from cold climates, such as the Alaskan Malamute, the Samoyed and the Siberian Husky, have a thick one.
Dogs shed the undercoat in large amounts seasonally, often in spring and autumn, and brushing with a rake or de-shedding comb removes the loose fur. Matted undercoat can trap moisture against the skin, so a dog groomer may be needed for dense coats.
Not every dog has an undercoat. Breeds with a smooth coat or a silky coat often have little or none. A full double coat is more than the undercoat alone, since it includes the outer guard hairs. Shaving is not a fix for shedding.
Last reviewed November 8, 2026