The Collaborative International Dictionary of English v.0.48:

Saturated \Sat"u*ra`ted\, a.
   1. Filled to repletion; holding by absorption, or in
      solution, all that is possible; as, saturated garments; a
      saturated solution of salt.
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   2. (Chem.) Having its affinity satisfied; combined with all
      it can hold; -- said of certain atoms, radicals, or
      compounds; thus, methane is a saturated compound.
      Contrasted with unsaturated.
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   Note: A saturated compound may exchange certain ingredients
         for others, but can not take on more without such
         exchange.
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   Saturated color (Optics), a color not diluted with white; a
      pure unmixed color, like those of the spectrum.
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