neodymium

noun2

1. •
   A chemical element (symbol Nd) with an atomic number of 60: a hard, slightly malleable silvery rare earth metal that quickly tarnishes in air and moisture.

   • Other rare elements, like neodymium, exist in more than one isotopic form, the ratios of which can provide a measure of the depth from which the flow material may ultimately have been derived. — 2004
2. •
   An atom of this element.