from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A silvery, moderately hard metallic element that constitutes approximately 3 percent of the earth's crust and is a basic component of most animals and plants. It occurs naturally in limestone, gypsum, and fluorite, and its compounds are used to make plaster, quicklime, Portland cement, and metallurgic and electronic materials. 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 Table at element.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A chemical element, atomic number 20, that is an alkaline earth metal and occurs naturally as carbonate in limestone and as silicate in many rocks.
from the GNU version of the Collaborative International Dictionary of English
- n. An elementary substance; a metal which combined with oxygen forms lime. It is of a pale yellow color, tenacious, and malleable. It is a member of the alkaline earth group of elements. Atomic weight 40. Symbol Ca.
from The Century Dictionary and Cyclopedia
- n. Chemical symbol, Ca; atomic weight, 40. A metal having a light-yellow color and brilliant luster, about as hard as gold, very ductile, and having a specific gravity of about 1.57.
- n. A calcium light.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. 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
Latin calx, calc-, lime; see calx + -ium.(American Heritage® Dictionary of the English Language, Fourth Edition)
A New Latin word derived by Sir Humphry Davy in 1808, from Latin calx ("lime", "limestone") because it occurs in limestone. (Wiktionary)