Calcium

n.
  1. 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.
    2. Calcium light ,
    an intense light produced by the incandescence of a stick or ball of lime in the flame of a combination of oxygen and hydrogen gases, or of oxygen and coal gas; -- called also Drummond light and lime light.