molybdenum Meaning, Definition & Usage

  1. noun a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel
    Mo; atomic number 42.

WordNet

Mol`yb*de"num noun
Etymology
NL.: cf. F. molybdène. See Molybdena.
Definitions
  1. (Chem.) A rare element of the chromium group, occurring in nature in the minerals molybdenite and wulfenite, and when reduced obtained as a hard, silver-white, difficulty fusible metal. Symbol Mo. Atomic weight 95.9.

Webster 1913