calcium

Etymology

A New Latin word derived by Sir Humphry Davy in 1808, from Latin calx ("lime", "limestone") because it occurs in limestone.^[1]

Pronunciation

• (US) IPA^(key): /ˈkælsi.əm/

• Audio (US)

  (file)

Noun

calcium (countable and uncountable, plural calciums) (Symbol: Ca)

1. 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.
   • 2013 September-October, Katie L. Burke, “In the News”, in American Scientist:

     Oxygen levels on Earth skyrocketed 2.4 billion years ago, when cyanobacteria evolved photosynthesis: […] . The evolutionary precursor of photosynthesis is still under debate, and a new study sheds light. The critical component of the photosynthetic system is the “water-oxidizing complex”, made up of manganese atoms and a calcium atom.

2. (countable) An atom of this element.

See also

• chalk
• lime
• limestone

Alternative forms

• kalcium

Noun

calcium

1. calcium

Pronunciation

• Audio

  (file)

Noun

calcium n (uncountable)

1. calcium

Pronunciation

• IPA^(key): /kal.sjɔm/

• Audio

  (file)

Noun

calcium m (uncountable)

1. calcium

Further reading

• “calcium” in le Trésor de la langue française informatisé (The Digitized Treasury of the French Language).

Pronunciation

• (Classical) IPA^(key): /ˈkal.ki.um/, [ˈkaɫ.ki.ũ]
• (Ecclesiastical) IPA^(key): /ˈkal.t͡ʃi.um/

Etymology 1

Form of calx.

Noun

calcium

1. genitive plural of calx

Etymology 2

Derived from calx, calcis (“chalk”) +‎ -ium (chemical element suffix).

Noun

calcium n (genitive calciī); second declension

1. (New Latin) calcium