The word nut comes from the Old English hnutu, from Germanic.

It is the general term used to refer to an edible kernel (fruit) encased in a hard or woody shell. It is generally preceded by the name of the tree, its country of origin, etc.:

> cashew nut, walnut, Macadamia nut, Brazil nut, hazelnut, etc.

Also note in the same family:

> almond, pistachio

Despite their name, peanuts are not true nuts. While nuts are technically fruits, peanuts are actually légumes.