1.A common metal of a reddish color, both ductile and malleable, and very tenacious. It is one of the best conductors of heat and electricity. Symbol Cu. Atomic weight 63.3. It is one of the most useful metals in itself, and also in its alloys, brass and bronze. Note: Copper is the only metal which occurs native abundantly in large masses; it is found also in various ores, of which the most important are chalcopyrite, chalcocite, cuprite, and malachite. Copper mixed with tin forms bell metal; with a smaller proportion, bronze; and with zinc, it forms brass, pinchbeck, and other alloys.
2.A coin made of copper; a penny, cent, or other minor coin of copper. (Colloq.) "My friends filled my pockets with coppers."
3.A vessel, especially a large boiler, made of copper.
4.pl. Specifically (Naut.), The boilers in the galley for cooking; as, a ship's coppers. Note: Copper is often used adjectively, commonly in the sense of made or consisting of copper, or resembling copper; as, a copper boiler, tube, etc. "All in a hot and copper sky." Note: It is sometimes written in combination; as, copperplate, coppersmith, copper-colored.
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