The Collaborative International Dictionary of English v.0.48:

Difference \Dif"fer*ence\, v. t. [imp. & p. p. Differenced; p.
   pr. & vb. n. Differencing.]
   To cause to differ; to make different; to mark as different;
   to distinguish.
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         Thou mayest difference gods from men.    --Chapman.
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         Kings, in receiving justice and undergoing trial, are
         not differenced from the meanest subject. --Milton.
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         So completely differenced by their separate and
         individual characters that we at once acknowledge them
         as distinct persons.                     --Sir W.
                                                  Scott.
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The Collaborative International Dictionary of English v.0.48:

Difference \Dif"fer*ence\, n. [F. diff['e]rence, L.
   differentia.]
   1. The act of differing; the state or measure of being
      different or unlike; distinction; dissimilarity;
      unlikeness; variation; as, a difference of quality in
      paper; a difference in degrees of heat, or of light; what
      is the difference between the innocent and the guilty?
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            Differencies of administration, but the same Lord.
                                                  --1 Cor. xii.
                                                  5.
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   2. Disagreement in opinion; dissension; controversy; quarrel;
      hence, cause of dissension; matter in controversy.
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            What was the difference? It was a contention in
            public.                               --Shak.
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            Away therefore went I with the constable, leaving
            the old warden and the young constable to compose
            their difference as they could.       --T. Ellwood.
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   3. That by which one thing differs from another; that which
      distinguishes or causes to differ; mark of distinction;
      characteristic quality; specific attribute.
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            The marks and differences of sovereignty. --Davies.
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   4. Choice; preference. [Obs.]
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            That now he chooseth with vile difference
            To be a beast, and lack intelligence. --Spenser.
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   5. (Her.) An addition to a coat of arms to distinguish the
      bearings of two persons, which would otherwise be the
      same. See Augmentation, and Marks of cadency, under
      Cadency.
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   6. (Logic) The quality or attribute which is added to those
      of the genus to constitute a species; a differentia.
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   7. (Math.) The quantity by which one quantity differs from
      another, or the remainder left after subtracting the one
      from the other.
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   Ascensional difference. See under Ascensional.

   Syn: Distinction; dissimilarity; dissimilitude; variation;
        diversity; variety; contrariety; disagreement; variance;
        contest; contention; dispute; controversy; debate;
        quarrel; wrangle; strife.
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WordNet (r) 3.0 (2006):

difference
    n 1: the quality of being unlike or dissimilar; "there are many
         differences between jazz and rock" [ant: sameness]
    2: a variation that deviates from the standard or norm; "the
       deviation from the mean" [syn: deviation, divergence,
       departure, difference]
    3: a disagreement or argument about something important; "he had
       a dispute with his wife"; "there were irreconcilable
       differences"; "the familiar conflict between Republicans and
       Democrats" [syn: dispute, difference, difference of
       opinion, conflict]
    4: a significant change; "the difference in her is amazing";
       "his support made a real difference"
    5: the number that remains after subtraction; the number that
       when added to the subtrahend gives the minuend [syn:
       remainder, difference]

Moby Thesaurus II by Grady Ward, 1.0:

360 Moby Thesaurus words for "difference":
   aberrance, aberrancy, aberration, abnormality, abnormity,
   about-face, accommodation, account, achievement, adaptation,
   adjustment, aggregate, agreement to disagree, alerion, alienation,
   alteration, amelioration, amorphism, amount, animal charge,
   annulet, anomalism, anomalousness, anomaly, antagonism, apostasy,
   argent, argument, argumentation, armorial bearings, armory, arms,
   asymmetry, azure, bad copy, bad likeness, balance, bandeau, bar,
   bar sinister, baton, bearings, bend, bend sinister, betterment,
   billet, blazon, blazonry, bordure, box score, break, broad arrow,
   cadency mark, camouflage, canton, capriciousness, cast, change,
   change of heart, changeability, changeableness, chaplet, character,
   characteristic, charge, chevron, chief, choppiness, clash,
   clashing, coat of arms, cockatrice, conflict, constructive change,
   contention, continuity, contradiction, contradistinction,
   contrariety, contrast, controversy, conversion, coronet, count,
   counter-culture, credit, crescent, crest, cross, cross moline,
   cross-purposes, crown, dappleness, defection, deficit,
   degeneration, degenerative change, derangement, deterioration,
   deviation, device, difference of opinion, differencing,
   differentiate, differentiation, difficulty, disaccord,
   disaccordance, disagreement, disapprobation, disapproval, discern,
   discontinuity, discord, discordance, discordancy, discrepancy,
   discriminate, disequilibrium, disguise, disharmony, disorder,
   disparity, disproportion, dispute, dissatisfaction, dissemblance,
   dissension, dissent, dissentience, dissidence, dissimilarity,
   dissimilation, dissimilitude, dissonance, distinction, distinguish,
   disunion, disunity, divarication, divergence, divergency,
   diversification, diversion, diversity, dividedness, division,
   dropping out, eagle, eccentricity, epact, ermine, ermines,
   erminites, erminois, erraticism, escutcheon, extricate, faction,
   falcon, fess, fess point, field, file, fitting, flanch,
   fleur-de-lis, flip-flop, fret, fur, fusil, garland, gradual change,
   griffin, gules, gyron, hatchment, helmet, heraldic device,
   heterogeneity, heteromorphism, honor point, idiosyncrasy,
   imbalance, impalement, impaling, improvement, inaccordance,
   inadequacy, incommensurability, incomparability, incongruity,
   inconsistency, inconstancy, inequality, inequity, inescutcheon,
   inferiority, injustice, instability, insufficiency, irregularity,
   jarring, jerkiness, label, leftovers, lion, lozenge, makeup,
   mantling, marshaling, martlet, mascle, melioration, mercuriality,
   mere caricature, metal, metamorphosis, minority opinion,
   misunderstanding, mitigation, modification, modulation,
   monstrosity, motleyness, motto, mullet, mutability, nature,
   negation, net, nombril point, nonagreement, nonassent,
   nonconcurrence, nonconformism, nonconformity, nonconsent,
   nonstandardization, nonuniformity, number, octofoil, odds,
   opposition, oppugnancy, or, ordinary, orle, otherness, overbalance,
   overthrow, pale, paly, pean, peculiarity, pheon, polarization,
   poor imitation, product, purpure, qualification, quantity, quarrel,
   quarter, quartering, radical change, raggedness, re-creation,
   realignment, reckoning, recusance, recusancy, redesign, reform,
   reformation, rejection, remainder, remaking, renewal, repudiation,
   repugnance, reshaping, rest, restructuring, reversal, revival,
   revivification, revolution, rose, sable, saltire, score, scutcheon,
   secession, separate, sever, severalize, shield, shift, shortcoming,
   spread eagle, strife, subnormality, subordinary, sudden change,
   sum, summation, superiority, surplus, switch, tale, tally, tenne,
   teratism, the bottom line, the story, the whole story, tincture,
   torse, total, total change, transformation, transition, tressure,
   turn, turnabout, unbalance, unconformism, unconformity,
   underground, unevenness, unfair discrimination, unharmoniousness,
   unicorn, unlikeness, unnaturalism, unnaturalness, unorthodoxy,
   unresemblance, unsameness, unsimilarity, unsteadiness, upheaval,
   vair, variability, variance, variation, variegation, variety,
   variousness, versatility, vert, violent change, wavering, whole,
   withdrawal, worsening, wreath, x number, yale



Bouvier's Law Dictionary, Revised 6th Ed (1856):

DIFFERENCE. A dispute, contest, disagreement, quarrel.