calcium

American  

[kal-see-uhm] / ˈkæl si əm /

noun

Chemistry, Biology.

• calciums
  plural

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.

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calcium British  

/ 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

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calcium Scientific  

/ 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

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Other Word Forms

Noun Inflected Forms

• calciums
  plural

Etymology

Origin of calcium

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

Example Sentences

See Examples For:

calcium calciums

"There are mandatory vitamins and minerals which manufacturers in the UK are required to add to white wheat flour such as calcium carbonate, niacin and thiamin," she says.

From BBC ● Sep. 26, 2026

"Nutrients such as vitamin D, iron and calcium are of particular concern during adolescence, when deficiencies may have lasting implications for skeletal health and overall development."

From Science Daily ● Sep. 24, 2026

For calcium supplements, that conclusion was based on moderate certainty evidence from 11 trials involving 9,067 participants.

From Science Daily ● Sep. 21, 2026

Still, the results remained broadly consistent when researchers accounted for factors including age, sex, previous fractures, previous falls, and average calcium intake from food.

From Science Daily ● Sep. 21, 2026

When the calcium oxide has softened the delicate inner skin, it’s peeled off slowly and carefully.

From "I Am Not Your Perfect Mexican Daughter" by Erika L. Sánchez

It appears to me that one of the calciums had flared up and the sparks ignited the lint on the curtain.

From Chicago's Awful Theater Horror by Various

The calciums had gradually been turning to the blue of moonlight, and now, at the back of the stage, Venus arose, veiled in a mist of foam.

From The Title Market by J. H. Gardner Soper

"I'll take the centre of the stage, and you will order calciums for one!"

From Vignettes of Manhattan; Outlines in Local Color by Brander Matthews

The picture is built up bit by bit; it is never flashed suddenly and completely as by best-seller calciums; it remains a bit dim at the end.

From A Book of Prefaces by H. L. (Henry Louis) Mencken