Nut (botany)

Nut (botany), term commonly and loosely applied to any dry, hard-shelled fruit or seed having a rind that can be easily separated from the internal, edible kernel. In botanical terminology, the term nut is restricted to a one-seeded fruit that has developed from a compound ovary, that has external walls hardened to a woody consistency, and that is indehiscent, which means that it does not split open to release its seed. Such so-called true nuts may be edible or inedible; common examples are acorns, beechnuts, chestnuts, and hazelnuts. Examples of fruits or seeds that are incorrectly and popularly termed nuts include almonds and walnuts, which are drupes with the fleshy outer layer removed; peanuts, which are seeds contained in pods; and horse chestnuts and Brazil nuts, which are seeds contained in capsules.