The Collaborative International Dictionary of English v.0.48:

Disparage \Dis*par"age\ (?; 48), v. t. [imp. & p. p.
   Disparaged; p. pr. & vb. n. Disparaging.] [OF.
   desparagier, F. d['e]parager, to marry unequally; pref. des-
   (L. dis-) + F. parage extraction, lineage, from L. par equal,
   peer. See Peer.]
   1. To match unequally; to degrade or dishonor by an unequal
      marriage. [Obs.]
      [1913 Webster]

            Alas! that any of my nation
            Should ever so foul disparaged be.    --Chaucer.
      [1913 Webster]

   2. To dishonor by a comparison with what is inferior; to
      lower in rank or estimation by actions or words; to speak
      slightingly of; to depreciate; to undervalue.
      [1913 Webster]

            Those forbidding appearances which sometimes
            disparage the actions of men sincerely pious. --Bp.
                                                  Atterbury.
      [1913 Webster]

            Thou durst not thus disparage glorious arms.
                                                  --Milton.

   Syn: To decry; depreciate; undervalue; underrate; cheapen;
        vilify; reproach; detract from; derogate from; degrade;
        debase. See Decry.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Disparage \Dis"pa*rage`\, n.
   Inequality in marriage; marriage with an inferior. [Obs.]
   --Chaucer.
   [1913 Webster]

         Dissuaded her from such a disparage.     --Spenser.
   [1913 Webster]

WordNet (r) 3.0 (2006):

disparage
    v 1: express a negative opinion of; "She disparaged her
         student's efforts" [syn: disparage, belittle, pick
         at] [ant: blandish, flatter]

Moby Thesaurus II by Grady Ward, 1.0:

157 Moby Thesaurus words for "disparage":
   abate, abrade, abstract, abuse, attaint, backbite, bad-mouth, bate,
   be above, be contemptuous of, be disrespectful,
   be overfamiliar with, belittle, bespatter, blacken, blot,
   blow upon, brand, bring down, bring into discredit, bring low,
   care nothing for, censure, cheapen, chill, contemn, criticize,
   cry down, curtail, debase, decrease, decry, deduct, defame, defile,
   degrade, deject, demean, demoralize, denigrate, deprecate,
   depreciate, deride, derogate, derogate from, despise, detract,
   detract from, devaluate, devalue, diminish, disapprove,
   disapprove of, discommend, discredit, disdain, disesteem, disgrace,
   dishearten, dishonor, dispirit, dispraise, disprize, disrespect,
   disvalue, downgrade, drain, dump on, eat away, erode, expose,
   expose to infamy, extract, feel contempt for, feel superior to,
   file away, gibbet, hang in effigy, hold beneath one, hold cheap,
   hold in contempt, impair, insult, knock, leach, lessen, libel,
   look down upon, make free with, make light of, make little of,
   make nothing of, malign, minimize, misestimate, misprize,
   not respect, pillory, purify, put down, rank low, reduce, refine,
   reflect discredit upon, remove, reprimand, retrench, ridicule,
   rub away, run down, scorn, sell short, set at naught,
   set little by, shorten, show disrespect for, shrug off, slander,
   slight, slur, smear, sneer at, sneeze at, sniff at, snort at, soil,
   speak ill of, stain, stigmatize, subduct, submit to indignity,
   subtract, sully, taint, take a liberty, take away, take from,
   take liberties with, talk down, tarnish, thin, thin out,
   think little of, think nothing of, traduce, treat with disrespect,
   trifle with, underestimate, underprize, underrate, underreckon,
   undervalue, vilify, wear away, weed, withdraw, write off