The Collaborative International Dictionary of English v.0.48:

Derogate \Der"o*gate\, v. t. [imp. & p. p. Derogated; p. pr. &
   vb. n. Derogating.] [L. derogatus, p. p. of derogare to
   derogate; de- + rogare to ask, to ask the people about a law.
   See Rogation.]
   1. To annul in part; to repeal partly; to restrict; to limit
      the action of; -- said of a law.
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            By several contrary customs, . . . many of the civil
            and canon laws are controlled and derogated. --Sir
                                                  M. Hale.
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   2. To lessen; to detract from; to disparage; to depreciate;
      -- said of a person or thing. [R.]
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            Anything . . . that should derogate, minish, or hurt
            his glory and his name.               --Sir T. More.
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