[AS.] A tree of large size, with alternate, pinnate leaves, found chiefly in North America. The black walnut is a beautiful timber tree found in the United States, with a heart-wood of a warm brown color, a favorite wood for furniture making. The nut is round and oily, enclosed in a hard shell with a fibrous outer covering. The white walnut is a North American tree with long oily nuts, and hence called butter-nut. It also yields a valuable wood. There are some species found in Asia, whose wood is used in cabinet making, and the nut used for dessert and pickling. The nut yields walnut oil used in cooking.