'hafnium' definitions:

Definition of 'hafnium'

(from WordNet)
noun
A grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons [syn: hafnium, Hf, atomic number 72]

Definition of 'hafnium'

From: GCIDE
  • hafnium \haf"ni*um\ (h[a^]f"n[=e]*[u^]m or h[aum]f"n[=e]*[u^]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 (2227[deg] C). It is used in nuclear reactors, and incandescent lamps as a scavenger of oxygen and nitrogen. See also norium. [1913 Webster]

Definition of 'hafnium'

From: Elements
  • 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.