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

tantalum \tan"talum\, n. nl. so named on account of the
   perplexity and difficulty encounterd by its discoverer
   ekeberg in isolating it. see tantalus. chem.
   a rare nonmetallic element found in certain minerals, as
   tantalite, samarskite, and fergusonite, and isolated as a
   dark powder which becomes steel-gray by burnishing. symbol
   ta. atomic weight 182.0. formerly called also tantalium.
   1913 webster
see also:
tantalus tantalium 

[2] : WordNet (r) 2.0

tantalum
     n : a hard gray lustrous metallic element that is highly
         corrosion-resistant; occurs in niobite and fergusonite
         and tantalite syn: ta, atomic number 73
see also:
ta atomic number 73 

[3] : Elements database 20001107

tantalum
symbol: ta
atomic number: 73
atomic weight: 180.948
heavy blue-grey metallic transition element. ta-181 is a stable isotope,
and ta-180 is a radioactive isotope, with a half-life in excess of 10^7
years. used in surgery as it is unreactive. forms a passive oxide layer in
air. identified in 1802 by ekeberg and isolated in 1820 by jons j.
berzelius.

Tantalum >> T Words
Tantalum, definition of term: Tantalum
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