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

unsaturated \unsat"ura`ted\, a.
   1. capable of absorbing or dissolving to a greater degree;
      as, an unsaturated solution.
      1913 webster

   2. chem. capable of taking up, or of uniting with, certain
      other elements or compounds, without the elimination of
      any side product; thus, aldehyde, ethylene, and ammonia
      are unsaturated; benzene has three unsaturated bonds. the
      term is applied most commonly to compounds with a double
      or triple bond between two carbon atoms as in ethylene.
      1913 webster +pjc

[2] : WordNet (r) 2.0

unsaturated
     adj 1: not saturated; capable of dissolving more of a substance at
            a given temperature; "an unsaturated salt solution"
            ant: saturated
     2: used of a compound especially of carbon containing atoms
        sharing more than one valence bond; "unsaturated fats"
        ant: saturated
     3: of color not chromatically pure; diluted; "an unsaturated
        red" ant: saturated
see also:
saturated 

Unsaturated >> U Words
Unsaturated, definition of term: Unsaturated
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