underfur

American  

[uhn-der-fur] / ˈʌn dərˌfɜr /

noun

1. the fine, soft, thick, hairy coat under the longer and coarser outer hair in certain animals, as seals, otters, and beavers.

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underfur British  

/ ˈʌndəˌfɜː /

noun

1. Also called: undercoat.  the layer of dense soft fur occurring beneath the outer coarser fur in certain mammals, such as the otter and seal

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Etymology

Origin of underfur

First recorded in 1875–80; under- + fur

Example Sentences

“The underfur is five times as dense as those guard hairs.”

From Washington Post • Oct. 16, 2022

But beneath those, there’s a much thicker layer of underfur.

From Washington Post • Oct. 16, 2022

“That underfur traps a layer of air, and that air gets warmed by the body,” she explains.

From Washington Post • Oct. 16, 2022

Silver moved in a halo of light, for the sun sparkled on the guard hairs that grew out over the dense underfur and she seemed to glow.

From "Julie of the Wolves" by Jean Craighead George

More than 200 impression slides and whole mounts of guard hair and underfur were prepared.

From Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado by Douglas, Charles L.