The cashew tree (Anacardium occidentale) is a tropical evergreen tree that produces the cashew seed and the cashew apple accessory fruit. The tree can grow as high as 14 m (46 ft), but the dwarf cultivars, growing up to 6 m (20 ft), prove more profitable, with earlier maturity and greater yields. The cashew seed is commonly considered a snack nut (cashew nut) eaten on its own, used in recipes, or processed into cashew cheese or cashew butter. Like the tree, the nut is often called cashew. Cashew allergies are triggered by the proteins found in tree nuts, and cooking often does not remove or change these proteins.
 

Nuts

A nut is a fruit composed of a hard shell and a seed, which is generally edible.

There is an additional requirement in botany that the shell does not open to release the seed (indehiscent). In a general context, a wide variety of dried seeds are called nuts, but in a botanical context, only ones that include the indehiscent fruit are considered true nuts.