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

hafnium \haf"nium\ ha^f"n=eu^m or haumf"n=eu^m,
   n.
   a metallic element of atomic number 72 present together with
   zirconium to the extent of 1 to 5 in zirconium minerals. it
   is a poisonous, ductile metal with a brilliant silver luster,
   has an atomic weight of 178.49, and has a high melting point
   2227deg c. it is used in nuclear reactors, and
   incandescent lamps as a scavenger of oxygen and nitrogen. see
   also norium.
   1913 webster
see also:
norium 

[2] : WordNet (r) 2.0

hafnium
     n : a gray tetravalent metallic element that resembles zirconium
         chemically and is found in zirconium minerals; used in
         filaments for its ready emission of electrons syn: hf,
          atomic number 72
see also:
hf atomic number 72 

[3] : Elements database 20001107

hafnium
symbol: hf
atomic number: 72
atomic weight: 178.49
silvery lustrous metallic transition element. used in tungsten alloys in
filaments and electrodes, also acts as a neutron absorber. first reported
by urbain in 1911, existence was finally established in 1923 by d. coster,
g.c. de hevesy in 1923.

Hafnium >> H Words
Hafnium, definition of term: Hafnium
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