The Collaborative International Dictionary of English v.0.48:

Distinguish \Dis*tin"guish\, v. t. [imp. & p. p.
   Distinguished; p. pr. & vb. n. Distinguishing.] [F.
   distinguer, L. distinguere, distinctum; di- = dis- +
   stinguere to quench, extinguish; prob. orig., to prick, and
   so akin to G. stechen, E. stick, and perh. sting. Cf.
   Extinguish.]
   1. Not set apart from others by visible marks; to make
      distinctive or discernible by exhibiting differences; to
      mark off by some characteristic.
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            Not more distinguished by her purple vest,
            Than by the charming features of her face. --Dryden.
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            Milton has distinguished the sweetbrier and the
            eglantine.                            --Nares.
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   2. To separate by definition of terms or logical division of
      a subject with regard to difference; as, to distinguish
      sounds into high and low.
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            Moses distinguished the causes of the flood into
            those that belong to the heavens, and those that
            belong to the earth.                  --T. Burnet.
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   3. To recognize or discern by marks, signs, or characteristic
      quality or qualities; to know and discriminate (anything)
      from other things with which it might be confounded; as,
      to distinguish the sound of a drum.
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            We are enabled to distinguish good from evil, as
            well as truth from falsehood.         --Watts.
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            Nor more can you distinguish of a man,
            Than of his outward show.             --Shak.
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   4. To constitute a difference; to make to differ.
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            Who distinguisheth thee?              --1 Cor. iv.
                                                  7. (Douay
                                                  version).
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   5. To separate from others by a mark of honor; to make
      eminent or known; to confer distinction upon; -- with by
      or for."To distinguish themselves by means never tried
      before." --Johnson.

   Syn: To mark; discriminate; differentiate; characterize;
        discern; perceive; signalize; honor; glorify.
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The Collaborative International Dictionary of English v.0.48:

Distinguished \Dis*tin"guished\, a.
   1. Marked; special.
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            The most distinguished politeness.    --Mad. D'
                                                  Arblay.
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   2. Separated from others by distinct difference; having, or
      indicating, superiority; eminent or known; illustrious; --
      applied to persons and deeds.

   Syn: Marked; noted; famous; conspicuous; celebrated;
        transcendent; eminent; illustrious; extraordinary;
        prominent. -- Distinguished, Eminent, Conspicuous,
        Celebrated, Illustrious. A man is eminent, when he
        stands high as compared with those around him;
        conspicuous, when he is so elevated as to be seen and
        observed; distinguished, when he has something which
        makes him stand apart from others in the public view;
        celebrated, when he is widely spoken of with honor and
        respect; illustrious, when a splendor is thrown around
        him which confers the highest dignity.
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WordNet (r) 3.0 (2006):

distinguished
    adj 1: (used of persons) standing above others in character or
           attainment or reputation; "our distinguished professor"
    2: used of a person's appearance or behavior; befitting an
       eminent person; "his distinguished bearing"; "the monarch's
       imposing presence"; "she reigned in magisterial beauty" [syn:
       distinguished, grand, imposing, magisterial]

Moby Thesaurus II by Grady Ward, 1.0:

195 Moby Thesaurus words for "distinguished":
   a cut above, above, absolute, acclaimed, ahead, appropriate,
   aristocratic, ascendant, assorted, at odds, at variance, august,
   better, capping, celebrated, certain, characteristic, chosen,
   concrete, conspicuous, contrary, contrasted, contrasting, courtly,
   crowned with laurel, defined, definite, departing, detailed,
   determinate, deviating, deviative, different, differentiated,
   differing, dignified, disaccordant, disagreeing, discordant,
   discrepant, discrete, discriminated, disjoined, disparate,
   dissimilar, dissonant, distinct, distinctive, distingue, divergent,
   diverging, divers, diverse, diversified, eclipsing, elevated,
   eminent, esoteric, especial, esteemed, estimable, exalted,
   exceeding, excellent, excelling, exceptional, express,
   extraordinary, fabled, famed, famous, far-famed, far-heard, finer,
   fixed, glorious, godlike, grand, great, greater, heroic,
   heterogeneous, high, higher, honorable, honored, idiocratic,
   idiosyncratic, illustrious, imposing, in ascendancy, in character,
   in disagreement, in the ascendant, inaccordant, incompatible,
   incongruous, inconsistent, inconsonant, individual, inharmonious,
   inner, intimate, intrinsic, irreconcilable, lauded, laureate,
   legendary, lofty, magnanimous, magnificent, majestic, major, many,
   marked, memorable, minute, motley, much acclaimed, multifarious,
   mythical, noble, notable, noted, noteworthy, notorious, of choice,
   of mark, of note, one up on, outstanding, over, particular,
   peculiar, personal, poles apart, poles asunder, popular, precise,
   prestigious, private, prominent, proper, quintessential, rare,
   regal, remarkable, rememberable, renowned, reputable, respected,
   respective, rivaling, royal, salient, separate, separated, several,
   signal, single, singular, soaring, solipsistic, special, specific,
   stately, striking, sublime, super, superb, superior, surpassing,
   talked-about, talked-of, telling, topping, towering, transcendent,
   transcendental, transcending, true to form, unconformable, unequal,
   unforgettable, unique, unlike, upper, variant, varied, variegated,
   various, varying, well-known, widely apart, worlds apart