The Collaborative International Dictionary of English v.0.48:

Castrate \Cas"trate\, v. t. [imp. & p. p. Castrated; p. pr. &
   vb. n. Castrating.] [L. castrarus, p; p. of castrare to
   castrate, asin to Skr. [,c]astra knife.]
   1. To deprive of the testicles; to emasculate; to geld; to
      alter.
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   2. To cut or take out; esp. to remove anything erroneous, or
      objectionable from, as the obscene parts of a writing; to
      expurgate.
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            My . . . correspondent . . . has sent me the
            following letter, which I have castrated in some
            places.                               --Spectator.
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