Source : Webster's Revised Unabridged Dictionary (1913)

Zirconium \Zir*co"ni*um\, n. [NL.] (Chem.)
   A rare element of the carbon-silicon group, intermediate
   between the metals and nonmetals, obtained from the mineral
   zircon as a dark sooty powder, or as a gray metallic
   crystalline substance. Symbol Zr. Atomic weight, 90.4.

Source : WordNet®

zirconium
     n : a lustrous gray strong metallic element resembling titanium;
         it is used in nuclear reactors as a neutron absorber; it
         occurs in baddeleyite but is obtained chiefly from zircon
         [syn: {Zr}, {atomic number 40}]