Sheep whose skin carries a high proportion of coarse hairs as opposed to fine wool hairs. The leather produced from these skins has a finer and tougher grain than that made from wool-bearing sheep, and as a result, the processed skin resembles that of the goat and they are frequently hard if not impossible to tell apart by visual means alone.
Roberts, Matt, Don Etherington, and Margaret R. Brown. 1982. Bookbinding and the conservation of books: a dictionary of descriptive terminology. Washington: Library of Congress.