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

saturation \sat`ura"tion\, n. l. saturatio: cf. f.
   saturation.
   1. the act of saturating, or the state of being saturating;
      complete penetration or impregnation.
      1913 webster

   2. chem. the act, process, or result of saturating a
      substance, or of combining it to its fullest extent.
      1913 webster

   3. optics freedom from mixture or dilution with white;
      purity; -- said of colors.
      1913 webster

   note: the degree of saturation of a color is its relative
         purity, or freedom from admixture with white.
         1913 webster

[2] : WordNet (r) 2.0

saturation
     n 1: the process of totally saturating something with a
          substance; "the impregnation of wood with preservative";
          "the saturation of cotton with ether" syn: impregnation
     2: the act of soaking thoroughly with a liquid
     3: a condition in which a quantity no longer responds to some
        external influence
     4: chromatic purity: freedom from dilution with white and hence
        vividness of hue syn: chroma, intensity, vividness
see also:
impregnation chroma intensity vividness 

[3] : Moby Thesaurus II by Grady Ward, 1.0

97 moby thesaurus words for "saturation":
   munsell chroma, technicolor, amplitude, bellyful, brewing,
   bright color, brightness, brilliance, chroma, chromatic color,
   chromaticity, color, color quality, colorfulness,
   colorimetric quality, congestion, cool color, decoction, drench,
   drenching, ducking, dunking, engorgement, fill, flood tide, full,
   fullness, gaiety, glut, gorgeousness, high tide, high water, hue,
   hyperemia, imbruement, imbuement, impletion, impregnation,
   infiltration, infusion, injection, instillation, instillment,
   intensity, interpenetration, leaching, lightness, lixiviation,
   maceration, marination, more than enough, neutral color,
   overbrimming, overburden, overcharge, overflow, overfreight,
   overfullness, overload, overspill, overweight, penetration,
   percolation, permeation, pervasion, plenitude, plethora, pulping,
   pure color, purity, repletion, richness, satiation, satiety,
   satisfaction, saturatedness, saturation point, seething, skinful,
   snootful, soak, soakage, soaking, sopping, souse, sousing,
   spring tide, steeping, suffusion, supersaturation, surcharge,
   surfeit, tint, tone, value, vividness, warm color

Saturation >> S Words
Saturation, definition of term: Saturation
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