The term "king nut" refers to a type of hickory tree found in the eastern United States. It produces a very large nut, which is similar to that of the shagbark hickory but bigger in size.
In more advanced discussions, especially in botany or ecology, you might find "king nut" used when studying different species of hickory trees or their ecological importance.
"King nut" is a specific term used in the context of botany to describe a large nut from a hickory tree. It is a useful word for discussing types of nuts and trees, especially in the eastern United States.