cerium Meaning, Definition & Usage

  1. noun a ductile grey metallic element of the lanthanide series; used in lighter flints; the most abundant of the rare-earth group
    atomic number 58; Ce.

WordNet

Ce"ri*um noun
Etymology
Named dy Berzelius in 1803 from the asteroid Ceres, then just discovered (1801).
Definitions
  1. (Chem.) A rare metallic element, occurring in the minerals cerite, allanite, monazite, etc. Symbol Ce. Atomic weight 141.5. It resembles iron in color and luster, but is soft, and both malleable and ductile. It tarnishes readily in the air.

Webster 1913