Undercoat 

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"Undercoat" redirects here, but this term is also used to mean a layer of paint below the top layer.

Down hairs, also called the ground hairs, are the very fine, fluffy hairs closest to the skin on some mammals. The hairs are short and crimped, which makes them highly efficient for trapping air and insulating the animal.

In the hobby of animal fancy, the down hair is collectively called the undercoat and may be important in judging the animal, particularly at conformation dog shows and cat shows.

See also

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