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

manganese \man`ganese"\, n. f. mangan`ese, it. manganese,
   sasso magnesio; prob. corrupted from l. magnes, because of
   its resemblance to the magnet. see magnet, and cf.
   magnesia. chem.
   an element obtained by reduction of its oxide, as a hard,
   grayish white metal, fusible with difficulty melting point
   1244deg c, but easily oxidized. its ores occur abundantly
   in nature as the minerals pyrolusite, manganite, etc. symbol
   mn. atomic number 25; atomic weight 54.938 c=12.011.
   1913 webster +pjc

   note: an alloy of manganese with iron called ferromanganese
         is used to increase the density and hardness of steel.
         1913 webster

   black oxide of manganese, manganese dioxide or manganese
   peroxide, or black manganese chem., a heavy black powder
      mno2, occurring native as the mineral pyrolusite, and
      valuable as a strong oxidizer; -- called also familiarly
      manganese. it colors glass violet, and is used as a
      decolorizer to remove the green tint of impure glass.
      1913 webster
see also:
magnet magnesia black oxide of manganese manganese dioxide manganese peroxide black manganese 
mno2 manganese 

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

mn \mn\, n. chem.
   the chemical symbol for manganese.
   pjc
see also:
manganese 

[3] : WordNet (r) 2.0

manganese
     n : a hard brittle gray polyvalent metallic element that
         resembles iron but is not magnetic; used in making steel;
         occurs in many minerals syn: mn, atomic number 25
see also:
mn atomic number 25 

[4] : Elements database 20001107

manganese
symbol: mn
atomic number: 25
atomic weight: 54.938
grey brittle metallic transition element. rather electropositive, combines
with some non-metals when heated. discovered in 1774 by scheele.

Manganese >> M Words
Manganese, definition of term: Manganese
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