The Collaborative International Dictionary of English v.0.48:

Saturate \Sat"u*rate\, v. t. [imp. & p. p. Saturated; p. pr. &
   vb. n. Saturating.] [L. saturatus, p. p. of saturare to
   saturate, fr. satur full of food, sated. See Satire.]
   1. To cause to become completely penetrated, impregnated, or
      soaked; to fill fully; to sate.
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            Innumerable flocks and herds covered that vast
            expanse of emerald meadow saturated with the
            moisture of the Atlantic.             --Macaulay.
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            Fill and saturate each kind
            With good according to its mind.      --Emerson.
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   2. (Chem.) To satisfy the affinity of; to cause to become
      inert by chemical combination with all that it can hold;
      as, to saturate phosphorus with chlorine.
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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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WordNet (r) 3.0 (2006):

saturated
    adj 1: being the most concentrated solution possible at a given
           temperature; unable to dissolve still more of a
           substance; "a saturated solution" [syn: saturated,
           concentrated] [ant: unsaturated]
    2: used especially of organic compounds; having all available
       valence bonds filled; "saturated fats" [ant: unsaturated]
    3: (of color) being chromatically pure; not diluted with white
       or grey or black [syn: saturated, pure] [ant:
       unsaturated]

Moby Thesaurus II by Grady Ward, 1.0:

121 Moby Thesaurus words for "saturated":
   SRO, allayed, awash, bathed, bloated, brimful, brimming, bulging,
   bursting, capacity, chock-full, choked, chuck-full, cloyed,
   congested, cram-full, crammed, crawling, creeping, crowded,
   deluged, dipped, disgusted, distended, drenched, dribbling,
   dripping, dripping wet, drowned, engorged, engulfed, farci, fed-up,
   filled, filled to overflowing, flooded, flush, full, full of,
   full to bursting, glutted, gorged, honeycombed, hyperemic,
   immersed, in spate, inundated, jaded, jam-packed, jammed,
   macerated, oozing, overblown, overburdened, overcharged, overfed,
   overflowed, overflowing, overfraught, overfreighted, overfull,
   overgorged, overladen, overloaded, oversaturated, overstocked,
   overstuffed, oversupplied, overweighted, packed,
   packed like sardines, permeated, plenary, plethoric,
   ready to burst, replete, round, running over, sated, satiated,
   satisfied, seeping, shot through, sick of, slaked, soaked, soaking,
   soaking wet, soaky, sodden, soggy, sopping, sopping wet, soppy,
   soused, standing room only, steeped, stuffed, stuffed up,
   submerged, submersed, supercharged, supersaturated, surcharged,
   surfeited, swamped, swarming, swollen, teeming, tired of, topful,
   waterlogged, watersoaked, weeping, weltering, wet, whelmed,
   with a bellyful, with a snootful, with enough of, wringing wet