Real Dictionary

hickory
variable noun: A hickory is a tree which has large leaves, greenish flowers, and nuts with smooth shells.

hickory in American English
any of a genus (Carya) of North American trees of the walnut family, with compound leaves, solid pith, and hard nuts
noun: any of several North American trees belonging to the genus Carya, of the walnut family, certain species of which bear edible nuts or yield a valuable wood

hickory in British English
noun: any juglandaceous tree of the chiefly North American genus Carya, having nuts with edible kernels and hard smooth shells