- any of a genus (Juglans) of trees of the walnut family, valued as shade trees, for their nuts, and for their wood, used in making furniture, paneling, etc.
- the edible nut of any of these trees, having a two-lobed seed
- their wood
- a shade of brown characteristic of the heartwood of the black walnut
Origin of walnutMiddle English walnot from Old English walhhnutu from wealh, foreign (see Welsh) + hnutu, nut