Dictionary.com
definitions
  • synonyms

calcium

[kal-see-uh m]
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. Symbol: Ca; atomic weight: 40.08; atomic number: 20; specific gravity: 1.55 at 20°C.
Show More

Origin of calcium

First recorded in 1800–10; calc- + -ium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for calcium

Contemporary Examples of calcium

Historical Examples of calcium


British Dictionary definitions for calcium

calcium

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
Show More

Word Origin for calcium

C19: from New Latin, from Latin calx lime
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for calcium

n.

coined 1808 by English chemist Sir Humphrey Davy (1778-1829), who first succeeded in isolating it, from Latin calx (genitive calcis) "limestone" (see chalk (n.)) + metallic element ending -ium.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper

calcium in Medicine

calcium

(kălsē-əm)
n. Symbol Ca
  1. A soft metallic element that is a basic component of animals and plants and constitutes approximately 3 percent of Earth's crust. It occurs naturally in limestone, gypsum, and fluorite. Atomic number 20.
Show More
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

calcium in Science

calcium

[kălsē-əm]
Ca
  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. See Periodic Table.
Show More
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.