The Collaborative International Dictionary of English v.0.48:

Abate \A*bate"\ ([.a]*b[=a]t"), v. t. [imp. & p. p. Abated, p.
   pr. & vb. n. Abating.] [OF. abatre to beat down, F.
   abattre, LL. abatere; ab or ad + batere, battere (popular
   form for L. batuere to beat). Cf. Bate, Batter.]
   1. To beat down; to overthrow. [Obs.]
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            The King of Scots . . . sore abated the walls.
                                                  --Edw. Hall.
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   2. To bring down or reduce from a higher to a lower state,
      number, or degree; to lessen; to diminish; to contract; to
      moderate; to cut short; as, to abate a demand; to abate
      pride, zeal, hope.
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            His eye was not dim, nor his natural force abated.
                                                  --Deut. xxxiv.
                                                  7.
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   3. To deduct; to omit; as, to abate something from a price.
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            Nine thousand parishes, abating the odd hundreds.
                                                  --Fuller.
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   4. To blunt. [Obs.]
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            To abate the edge of envy.            --Bacon.
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   5. To reduce in estimation; to deprive. [Obs.]
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            She hath abated me of half my train.  --Shak.
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   6. (Law)
      (a) To bring entirely down or put an end to; to do away
          with; as, to abate a nuisance, to abate a writ.
      (b) (Eng. Law) To diminish; to reduce. Legacies are liable
          to be abated entirely or in proportion, upon a
          deficiency of assets.
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   To abate a tax, to remit it either wholly or in part.
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