The Collaborative International Dictionary of English v.0.48:

Subdue \Sub*due"\, v. t. [imp. & p. p. Subdued; p. pr. & vb.
   n. Subduing.] [OE. soduen, OF. sosduire to seduce, L.
   subtus below (fr. sub under) + ducere to lead. See Duke,
   and cf. Subduct.]
   1. To bring under; to conquer by force or the exertion of
      superior power, and bring into permanent subjection; to
      reduce under dominion; to vanquish.
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            I will subdue all thine enemies.      --1 Chron.
                                                  xvii. 10.
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   2. To overpower so as to disable from further resistance; to
      crush.
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            Nothing could have subdued nature
            To such a lowness, but his unkind daughters. --Shak.
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            If aught . . . were worthy to subdue
            The soul of man.                      --Milton.
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   3. To destroy the force of; to overcome; as, medicines subdue
      a fever.
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   4. To render submissive; to bring under command; to reduce to
      mildness or obedience; to tame; as, to subdue a stubborn
      child; to subdue the temper or passions.
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   5. To overcome, as by persuasion or other mild means; as, to
      subdue opposition by argument or entreaties.
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   6. To reduce to tenderness; to melt; to soften; as, to subdue
      ferocity by tears.
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   7. To make mellow; to break, as land; also, to destroy, as
      weeds.
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   8. To reduce the intensity or degree of; to tone down; to
      soften; as, to subdue the brilliancy of colors.
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   Syn: To conquer; overpower; overcome; surmount; vanquish. See
        Conquer.
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Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "subduing":
   Cadmean victory, KO, Pyrrhic victory, Waterloo, abating, allaying,
   alleviating, alleviative, analgesic, anesthetic, anodyne,
   ascendancy, assuaging, assuasive, balmy, balsamic, beating,
   benumbing, blunting, cathartic, championship, chastening,
   cleansing, collapse, conquering, conquest, crash, cushioning,
   dampening, damping, deadening, deathblow, debacle, defeat,
   demulcent, destruction, diminishing, downfall, drubbing, dulling,
   easing, easy victory, emollient, failure, fall, grand slam, hiding,
   knockout, lambasting, landslide, landslide victory, lathering,
   lenitive, lessening, licking, loosening, mastery, mitigating,
   mitigative, mollifying, moral victory, numbing, overcoming,
   overthrow, overturn, pain-killing, palliative, picnic, purgative,
   pushover, quietus, reducing, relaxing, relieving, remedial, ruin,
   runaway victory, smash, softening, soothing, subdual, subjugation,
   success, tempering, thrashing, total victory, trimming, triumph,
   trouncing, undoing, vanquishment, victory, walkaway, walkover,
   whipping, win, winning, winning streak