Calcium
WordNet
noun
(1) 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
WiktionaryText
Etymology
A word derived by Sir Humphry Davy in 1808, from calx ("lime", "limestone") because it occurs in limestone.
Noun
(Symbol: Ca)
- 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.