Nut
2 of the 7 encyclopedias on this shelf carry an entry for Nut. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
in common language, any hard shelled, oily fruit. Botanically, a nut is a hard, dry, one-seeded fruit, in which but one ovule has developed. The shell does not split on ripening. Walnuts, hickory nuts, acorns, cocoanuts, chestnuts, and hazelnuts are familiar botanical nuts. Peanuts, Brazil nuts, and almonds are not nuts in this sense of the word. Like the common grains, nuts remain sweet a long time if kept dry. Now that our native forests are so restricted in area, and our population has so increased, the autumn joy of gathering nuts for winter use and the winter pleasure of eating nuts of one's own gathering have become almost a matter of tradition; but commercially, and as articles of food, nuts are gaining rapidly. About $9,000,000 worth are imported annually into the United States . We import almonds, cocoanuts, walnuts, and filberts. We export hickory nuts, black walnuts, pecans, and chestnuts. Mexico ships fifty car loads of pecans to the United States yearly. Nuts contain water, starch, sugar and fat. The average nut contains about sixty-five per cent of fat. In some parts of the world the people live almost entirely on nuts. See Pecan ; Almond ; Betel ; Brazil Nut ; Cocoanut ; Chestnut ; Hazelnut; Hickory ; Nutmeg ; Nux Vomica ; Walnut
Collier's New Encyclopedia (1921)
the name popularly given to the roundish fruit of certain trees and shrubs, consisting of a hard shell inclosing a kernel; as, a walnut, a cocoanut, a hazelnut, etc. In the United States, as in England, the name nut, without distinctive prefix, is commonly given to the hazelnut, but in France to the walnut. In mechanism, a short internal screw, which acts in the head of an external screw. and is employed to fasten anything that may become between it and a flange on the bottom of the external screw or bolt. A piece of metal with a cylindrical grooved hole, screwed upon the end of a screw bolt. In nautics, a projecting nozzle on each side of the shank of an anchor, to hold the stock firmly in its place.