The Collaborative International Dictionary of English v.0.48:

Neutralize \Neu"tral*ize\, v. t. [imp. & p. p. Neutralized; p.
   pr. & vb. n. Neutralizing.] [Cf. F. neutraliser.]
   1. To render neutral; to reduce to a state of neutrality.
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            So here I am neutralized again.       --Sir W.
                                                  Scott.
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   2. (Chem.) To render inert or imperceptible the peculiar
      affinities of, as a chemical substance; to destroy the
      effect of; as, to neutralize an acid with a base.
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   3. To destroy the peculiar properties or opposite
      dispositions of; to reduce to a state of indifference or
      inefficiency; to counteract; to render ineffective; as, to
      neutralize parties in government; to neutralize efforts,
      opposition, etc.
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            Counter citations that neutralize each other. --E.
                                                  Everett.
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WordNet (r) 3.0 (2006):

neutralized
    adj 1: made neutral in some respect; deprived of distinctive
           characteristics [syn: neutralized, neutralised]