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; [syn: calcium, Ca, atomic number 20]
WordNet (r) 3.0 (2006):
atomic number 20
n 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 [syn:
calcium, Ca, atomic number 20]