- black walnut, black walnut tree, black hickory, Juglans nigra - North American walnut tree with hard dark wood and edible nut
--1 is a kind of walnut, walnut tree
--1 is a member of Juglans, genus Juglans
--1 has parts: black walnut - black walnut - American walnut having a very hard and thick woody shell
--2 is a kind of walnut
--2 is a part of black walnut, black walnut tree, black hickory, Juglans nigra