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

magnesium \magne"sium\, n. nl.  f. see magnesia. chem.
   a light silver-white metallic element of atomic number 12,
   malleable and ductile, quite permanent in dry air but
   tarnishing in moist air. it burns, forming the oxide
   magnesia, with the production of a blinding light the
   so-called magnesium light which is used in signaling, in
   pyrotechny, or in photography where a strong actinic
   illuminant is required. its compounds occur abundantly, as in
   dolomite, talc, meerschaum, etc. symbol mg. atomic weight,
   24.305. specific gravity, 1.75.
   1913 webster

   magnesium sulphate. chem. same as epsom salts.
      1913 webster
see also:
magnesia magnesium sulphate epsom salts 

[2] : WordNet (r) 2.0

magnesium
     n : a light silver-white ductile bivalent metallic element; in
         pure form it burns with brilliant white flame; occurs
         naturally only in combination as in magnesite and
         dolomite and carnallite and spinel and olivine syn: mg,
          atomic number 12
see also:
mg atomic number 12 

[3] : Elements database 20001107

magnesium
symbol: mg
atomic number: 12
atomic weight: 24.312
silvery metallic element belonging to group 2 of the periodic table
alkaline-earth metals. it is essential for living organisms, and is used
in a number of light alloys. chemically very reactive, it forms a
protective oxide coating when exposed to air and burns with an intense
white flame. it also reacts with sulphur, nitrogen and the halogens. first
isolated by bussy in 1828.

Magnesium >> M Words
Magnesium, definition of term: Magnesium
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Magnesium Sulfa >> M Words
Magnesium Sulfa, definition of term: Magnesium Sulfa
magnesium+sulfa_pag1.html

Magnesium Oxide >> M Words
Magnesium Oxide, definition of term: Magnesium Oxide
magnesium+oxide_pag1.html