The Collaborative International Dictionary of English v.0.48:

Revert \Re*vert"\, v. t. [imp. & p. p. Reverted; p. pr. & vb.
   n. Reverting.] [L. revertere, reversum; pref. re- re- +
   vertere to turn: cf. OF. revertir. See Verse, and cf.
   Reverse.]
   1. To turn back, or to the contrary; to reverse.
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            Till happy chance revert the cruel scence. --Prior.
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            The tumbling stream . . .
            Reverted, plays in undulating flow.   --Thomson.
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   2. To throw back; to reflect; to reverberate.
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   3. (Chem.) To change back. See Revert, v. i.
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   To revert a series (Alg.), to treat a series, as y = a + bx
      + cx^2 + etc., where one variable y is expressed in
      powers of a second variable x, so as to find therefrom the
      second variable x, expressed in a series arranged in
      powers of y.
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WordNet (r) 3.0 (2006):

reverting
    adj 1: tending to return to an earlier state [syn: returning,
           reverting]
    n 1: a failure to maintain a higher state [syn: backsliding,
         lapse, lapsing, relapse, relapsing, reversion,
         reverting]