The Collaborative International Dictionary of English v.0.48:

Averse \A*verse"\, a. [L. aversus, p. p. of avertere. See
   Avert.]
   1. Turned away or backward. [Obs.]
      [1913 Webster]

            The tracks averse a lying notice gave,
            And led the searcher backward from the cave.
                                                  --Dryden.
      [1913 Webster]

   2. Having a repugnance or opposition of mind; disliking;
      disinclined; unwilling; reluctant.
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            Averse alike to flatter, or offend.   --Pope.
      [1913 Webster]

            Men who were averse to the life of camps.
                                                  --Macaulay.
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            Pass by securely as men averse from war. --Micah ii.
                                                  8.
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   Note: The prevailing usage now is to employ to after averse
         and its derivatives rather than from, as was formerly
         the usage. In this the word is in agreement with its
         kindred terms, hatred, dislike, dissimilar, contrary,
         repugnant, etc., expressing a relation or an affection
         of the mind to an object.
         [1913 Webster]

   Syn: Averse, Reluctant, Adverse.

   Usage: Averse expresses an habitual, though not of necessity
          a very strong, dislike; as, averse to active pursuits;
          averse to study. Reluctant, a term of the of the will,
          implies an internal struggle as to making some
          sacrifice of interest or feeling; as, reluctant to
          yield; reluctant to make the necessary arrangements; a
          reluctant will or consent. Adverse denotes active
          opposition or hostility; as, adverse interests;
          adverse feelings, plans, or movements; the adverse
          party.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Averse \A*verse"\, v. t. & i.
   To turn away. [Obs.] --B. Jonson.
   [1913 Webster]

WordNet (r) 3.0 (2006):

averse
    adj 1: (usually followed by `to') strongly opposed;
           "antipathetic to new ideas"; "averse to taking risks";
           "loath to go on such short notice"; "clearly indisposed
           to grant their request" [syn: antipathetic,
           antipathetical, averse(p), indisposed(p),
           loath(p), loth(p)]

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "averse":
   abhorrent, afraid, allergic, anti, antipathetic, at odds,
   averse to, backward, balky, contrary, cursory, differing,
   disaffected, disagreeing, disenchanted, disgusted, disinclined,
   disobedient, displeased, forced, fractious, hating, hesitant,
   hostile, ill-disposed, indisposed, indocile, involuntary, loath,
   loathing, mutinous, not charmed, opposed, perfunctory, perverse,
   put off, quailing, recalcitrant, recoiling, refractory, reluctant,
   resistant, shrinking, sulky, sullen, uncongenial, unconsenting,
   uneager, unfriendly, unsympathetic, unwilling