Calcium

n. (Ca) silvery metallic element present in the earth as well as in most animals and plants

Calcium (IPA: ) is the chemical element in the periodic table that has the symbol Ca and atomic number 20. It has an atomic mass of 40.078. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element in the Earth's crust. It is essential for living organisms, particularly in cell physiology, and is the most common metal in many animals.
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Calcium /cal·ci·um/ a chemical element, at. no. 20. Calcium phosphate salts form the dense hard material of teeth and bones. [more]Calcium - Community and Resources

Noun
1. 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
(synonym) Ca, atomic number 20
(hypernym) metallic element, metal
(hyponym) calcium ion, factor IV
(substance-holonym) calcium oxide, quicklime, lime, calx, calcined lime, fluxing lime, unslaked lime, burnt lime
(derivation) calcify

n. calcium, silvery metallic element present in the earth as well as in most animals and plants, Ca