The Collaborative International Dictionary of English v.0.48:

Purgament \Pur"ga*ment\, n. [L. purgamentum offscourings,
   washings, expiatory sacrifice. See Purge.]
   1. That which is excreted; excretion. [Obs.]
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   2. (Med.) A cathartic; a purgative. [Obs.] --Bacon.
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