calcium

[ kal-see-uhm ]

noun

, Chemistry, Biology.

1. a silver-white divalent metal, occurring combined in limestone, chalk, gypsum, etc., occurring also in vertebrates and other animals, as a component of bone, skeletal mass, shell, etc., and as a necessary element in nerve conduction, heartbeat, muscle contraction, and many other physiological functions. : Ca; : 40.08; : 20; : 1.55 at 20°C.

calcium

/ ˈkælsɪəm /

noun

1. a malleable silvery-white metallic element of the alkaline earth group; the fifth most abundant element in the earth's crust (3.6 per cent), occurring esp as forms of calcium carbonate. It is an essential constituent of bones and teeth and is used as a deoxidizer in steel. Symbol: Ca; atomic no: 20; atomic wt: 40.078; valency: 2; relative density: 1.55; melting pt: 842±2°C; boiling pt: 1494°C

calcium

/ kăl′sē-əm /

1. A silvery-white, moderately hard metallic element of the alkaline-earth group that occurs in limestone and gypsum. It is a basic component of leaves, bones, teeth, and shells, and is essential for the normal growth and development of most animals and plants. Calcium is used to make plaster, cement, and alloys. Atomic number 20; atomic weight 40.08; melting point 842 to 848°C; boiling point 1,487°C; specific gravity 1.55; valence 2.
2. See Periodic Table

Word History and Origins

Origin of calcium¹

First recorded in 1800–10; calc- + -ium

Word History and Origins

Origin of calcium¹

C19: from New Latin, from Latin calx lime

Example Sentences

I take calcium and vitamin D supplements, but prescription medications are generally only for women in menopause.

From The Daily Beast

Fat-free or skim milkEveryone knows milk is an excellent source of calcium that will keep your bones in tip-top shape.

From The Daily Beast

Feel good about using cottage cheese as a dip because it delivers calcium, quality protein and potassium.

From The Daily Beast

The rhino beetle—fried, stewed, grilled, or roasted—is high in calcium and protein.

From The Daily Beast

Excess calcium causing zinc and iron deficiency offers just one simple illustration of this kind of interaction.

From The Daily Beast

Crystals of calcium oxalate are insoluble in acetic acid or caustic soda.

From Project Gutenberg

The long axis of the hip-roof crystal is often so shortened that it resembles the envelop crystal of calcium oxalate.

From Project Gutenberg

The usual forms are: (a) Ammoniomagnesium phosphate crystals; (b) acid calcium phosphate crystals; and (c) amorphous phosphates.

From Project Gutenberg

Characteristic octahedral crystals of calcium oxalate (Fig. 47) appear after ingestion of certain vegetables.

From Project Gutenberg

The lights were lowered, a single calcium playing with its soft and silvery  rays upon his face and shoulders.

From Project Gutenberg