Толковый словарь английского языка Oxford English Reference - calcium

n. a soft grey metallic element of the alkaline earth group occurring naturally in limestone, marble, chalk, etc., that is important in industry and essential for normal growth in living organisms. Usage Symb.: Ca. Phrases and idioms calcium carbide a greyish solid used in the production of acetylene. calcium carbonate a white insoluble solid occurring naturally as chalk, limestone, marble, and calcite, and used in the manufacture of lime and cement. calcium hydroxide a white crystalline powder used in the manufacture of plaster and cement; slaked lime. calcium oxide a white crystalline solid from which many calcium compounds are manufactured: also called QUICKLIME, CALX. calcium phosphate the main constituent of animal bones and used as bone ash fertilizer. calcium sulphate a white crystalline solid occurring as anhydrite and gypsum. Etymology: L CALX lime + -IUM