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

When pain signals are passed along the nervous system, proteins called calcium channels play a key role.

From Science Daily

Flour is already fortified with calcium, niacin, thiamine and iron as a means of improving public health.

From BBC

The balls had a firm surface - hardened partially by accumulating sand and minerals like calcium - and a soft core.

From BBC

With chemical properties exceedingly similar to typical nutrients like iron and calcium, toxic metals look virtually the same to the body.

From Los Angeles Times

“They strip the calcium from your bones as they grow inside you,” she tells her therapist.

From Los Angeles Times