The Collaborative International Dictionary of English v.0.48:

Mort \Mort\, n. [F., death, fr. L. mors, mortis.]
   1. Death; esp., the death of game in the chase.
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   2. A note or series of notes sounded on a horn at the death
      of game.
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            The sportsman then sounded a treble mort. --Sir W.
                                                  Scott.
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   3. The skin of a sheep or lamb that has died of disease.
      [Prov. Eng. & Scot.]
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   Mort cloth, the pall spread over a coffin; black cloth
      indicative or mourning; funeral hangings. --Carlyle.

   Mort stone, a large stone by the wayside on which the
      bearers rest a coffin. [Eng.] --H. Taylor.
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