nut

Dry, hard, one-seeded fruit consisting of a kernel, usually oily, surrounded by a hard or brittle shell that does not split open at maturity. Nuts include chestnuts, filberts, and walnuts; but other so-called nuts are botanically seeds (Brazil nut, pistachio), legumes (peanut), or drupes (almond and coconut). Most edible nuts are well known as dessert nuts. Some nuts are sources of oil or fat. Not all nuts are edible; some are used for ornament.

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