gadolinium(n = noun.substance) atomic number 64, gd - a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group;
is a kind of metal, metallic element

   A rare earth metallic element of the Lanthanide series, with a characteristic spectrum, found associated with yttrium and other rare earth elements. Symbol, Gd; it has an atomic number of 64, an atomic weight of 157.25 (C=12.011), and a valence of +3. [1913 Webster]

gadolinium, n. Chem. a soft silvery metallic element of the lanthanoid series, occurring naturally in gadolinite.

Usage:
Symb.: Gd.

Etymology:
mod.L f. GADOLINITE