wool sponge

noun
  1. a commercial sponge, Hippiospongia lachne, of Florida and the West Indies, the surface of which resembles the fleece of a sheep.

Origin of wool sponge

An Americanism dating back to 1875–80
Also called sheepswool sponge.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018