The Collaborative International Dictionary of English v.0.48:

Discommon \Dis*com"mon\, v. t.
   1. To deprive of the right of common. [R.] --Bp. Hall.
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   2. To deprive of privileges. [R.] --T. Warton.
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   3. (Law) To deprive of commonable quality, as lands, by
      inclosing or appropriating. --Burrill.
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