Calcium Definition

kălsē-əm

noun

A soft, silver-white, metallic chemical element, one of the alkaline-earth metals, found in limestone, marble, chalk, etc., always in combination: it is used as a reducing agent and in fertilizer, and is the essential part of bones, shells, and teeth: symbol, Ca; at. no. 20

Webster's New World

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.

Wiktionary

(countable) An atom of this element.

Wiktionary

(physics) Tha major stable isotope of calcium, ⁴⁰₂₀Ca, having twenty protons and twenty neutrons; it amounts to almost 97% of the element in nature.

Wiktionary

(physics) A minor stable isotope of calcium, ⁴²₂₀Ca, having twenty protons and twenty-two neutrons; it amounts to about 0.6% of the element in nature.

Wiktionary

Synonyms:

Synonyms:
ca
atomic number 20

Other Word Forms of Calcium

Noun

Singular:

calcium

Plural:

calciums

Origin of Calcium

A New Latin word derived by Sir Humphry Davy in 1808, from Latin calx ("lime", "limestone") because it occurs in limestone.

From Wiktionary
Latin calx calc- lime calx –ium

From American Heritage Dictionary of the English Language, 5th Edition