pine nut or piñon, edible seed of various species of pine trees. Among the North American species that bear such edible seeds are the nut pines or piñons, Pinus edulis and P. monophylla, and the Digger pine, P. sabiniana, named after the Diggers of California. The nuts have a thin red-brown shell and range in size from about 3/4 in. (1.91 cm) to about 11/2 in. (3.75 cm). Pine nuts, or Indian nuts, were an important food for some early Native Americans and are still harvested in quantity both for food and for trading. They are picked from the ground, taken from squirrel caches, or extracted by hand from the cones. Some pine stands are in danger of depletion because insufficient seeds are left for reproduction. Pignolia nuts are the seeds of P. pinea of S Europe, where they are cultivated and much used for food. Quantities are exported to be used salted and in confectionery. Seeds of numerous other European and Asian pines are gathered under many local names. The name pignolia is often applied to all pine nuts and vice versa.

nut, in botany, a dry one-seeded fruit which is indehiscent (i.e., does not split open along a definite seam at maturity). Among the true nuts are the acorn, chestnut, and hazelnut. Commonly the word nut is used for any seed or fruit having an edible kernel surrounded by a hard or brittle covering. Thus the peanut pod is actually a legume, the Brazil nut is a seed enclosed with others in a capsule, and the almond is part of a drupe, a type of fruit that includes olives and peaches. Others that are not botanically true nuts are the cashew, coconut, litchi, pistachio, and walnut. Most nuts have a high content of oil; in addition they may contain substantial amounts of protein, carbohydrates, minerals, and vitamins. Although nuts were originally harvested from wild trees, this century has seen the increasing cultivation of nut orchards—especially in warmer climates—for commercial production both for food and for byproducts.

ivory nut: see tagua.

coquilla nut [Span.,=little coconut], fruit of a Brazilian palm (Attalea funifera), closely related to the coconut palm. Its fruit, 3 to 4 in. (7.6-10.2 cm) long, is very hard, of a richly streaked brown, and capable of taking a fine polish; it is used in cabinetwork and for umbrella handles. More important economically is the stiff, wiry, bright chocolate-colored leaf fiber, called piassava or piassaba, obtained from this and similar palms. It is used in making brooms and rope, and is an important export product in Amazonian South America. The nut is also a source of palm oil. Coquilla nuts are classified in the division Magnoliophyta, class Liliopsida, order Arecales, family Arecacae (Palmae).

Queensland nut: see macadamia.

Nut, in Egyptian religion, sky-goddess. She was the sister-wife of the earth god Geb, to whom she bore Osiris, Isis, Set, and Nephthys. She was sometimes represented with her hands and feet on the earth and the curve of her body forming the vault of heaven.

Indian nut: see pine nut.

Brazil nut, common name for the Lecythidaceae, a family of tropical trees. It includes the anchovy pear (Grias cauliflora), a West Indian species with edible fruit used for pickles, and several lumber trees of South America, e.g., the cannon-ball tree (Couroupita guianensis), some species of Barringtonia, and the Brazil nut (Bertholletia excelsa). The latter is found chiefly in Brazil along the Amazon and Orinoco rivers, but extensive groves have also been planted in N Bolivia. The edible Brazil nuts grow clumped together in large, round, woody and extremely hard seed pods the size of a large grapefruit. The meat of the seed (the "nut") is very rich in oil. The Brazil nut family is classified in the division Magnoliophyta, class Magnoliopsida, order Lecythidales.

In technology, a fastening device consisting of a square or hexagonal block, usually of metal, with a hole in the centre having internal, or female, threads that fit on the male threads of an associated bolt or screw. Bolts or screws with nuts are widely used for fastening machine and structural components. Seealso fastener.

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or cola nut

Caffeine-containing nut of two evergreen trees (Cola acuminata and C. nitida) of the cocoa family (Sterculiaceae), native to tropical Africa and cultivated extensively in the New World tropics. The trees grow to 60 ft (18.3 m) in height and have oblong leathery leaves, yellow flowers, and star-shaped fruit. The nut has been used in medicines and in soft drinks, though American “colas” today instead use synthetic flavorings that mimic its taste. Kola nuts are also used where grown as a medium of exchange or are chewed to diminish sensations of hunger and fatigue, to aid digestion, and to combat intoxication, hangover, and diarrhea.

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Edible seed of a large South American tree, Bertholletia excelsa (family Lecythidaceae), and one of the major commercially traded nuts in the world. The hard-walled fruit, resembling a large coconut, contains 8–24 nuts (seeds) arranged in it like sections of an orange. Each nut has a very hard shell and is three-sided in shape. Brazil nuts are high in fat and protein and taste somewhat like almond or coconut. The tree grows wild in stands in the Amazon River basin, reaching heights of 150 ft (45 m) or more.

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