The Collaborative International Dictionary of English v.0.48:

Purpuric \Pur*pu"ric\, a. [Cf. F. purpurique.]
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   1. (Med.) Of or pertaining to purpura. --Dunglison.
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   2. (Chem.) Pertaining to or designating, a nitrogenous acid
      contained in uric acid. It is not known in the pure state,
      but forms well-known purple-red compounds (as murexide),
      whence its name.
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   Note: Purpuric acid was formerly used to designate murexan.
         See Murexan.
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