[1] : The Collaborative International Dictionary of English v.0.48

zirconium \zirco"nium\, 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.
   1913 webster

[2] : WordNet (r) 2.0

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
see also:
zr atomic number 40 

[3] : Elements database 20001107

zirconium
symbol: zr
atomic number: 40
atomic weight: 91.22
grey-white metallic transition element. five natural isotopes and six
radioactive isotopes are known. used in nuclear reactors for a neutron
absorber. discovered in 1789 by martin klaproth, isolated in 1824 by
berzelius.


see also:
neutron 

Zirconium >> Z Words
Zirconium, definition of term: Zirconium
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