also butter-nut, 1753, nut of the white walnut, a North American tree; transferred to the tree itself from 1783. The nut's color was a brownish-gray, hence the word was used (1861) to describe the warm gray color of the Southern army uniforms in the American Civil War.
英英释意
1. North American walnut tree having light-brown wood and edible nuts; source of a light-brown dye
2. oily egg-shaped nut of an American tree of the walnut family
