The Collaborative International Dictionary of English v.0.48:

Defecate \Def"e*cate\, v. t. [imp. & p. p. Defecated; p. pr. &
   vb. n. Defecating.]
   1. To clear from impurities, as lees, dregs, etc.; to
      clarify; to purify; to refine.
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            To defecate the dark and muddy oil of amber.
                                                  --Boyle.
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   2. To free from extraneous or polluting matter; to clear; to
      purify, as from that which materializes.
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            We defecate the notion from materiality. --Glanvill.
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            Defecated from all the impurities of sense. --Bp.
                                                  Warburton.
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