The Collaborative International Dictionary of English v.0.48:

Peruvian \Pe*ru"vi*an\, a. [Cf. F. p['e]ruvien, Sp. peruviano.]
   Of or pertaining to Peru, in South America. -- n. A native or
   an inhabitant of Peru.
   [1913 Webster]

   Peruvian balsam. See Balsam of Peru, under Balsam.

   Peruvian bark, the bitter bark of trees of various species
      of Cinchona. It acts as a powerful tonic, and is a remedy
      for malarial diseases. This property is due to several
      alkaloids, as quinine, cinchonine, etc., and their
      compounds; -- called also Jesuit's bark, and cinchona.
      See Cinchona.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Peruvian bark
    n 1: medicinal bark of cinchona trees; source of quinine and
         quinidine [syn: cinchona, cinchona bark, Peruvian
         bark, Jesuit's bark]