noun. any of a class of drugs that block the flow of the electrolyte calcium (either in nerve cell conduction or smooth muscle contraction of the heart); has been used in the treatment of angina or arrhythmia or hypertension or migraine.
noun. a compound used as a fertilizer and as a source of nitrogen compounds.
noun. ['ˈkælsiːəm'] a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals.