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]