The Collaborative International Dictionary of English v.0.48:

Nepenthes \Ne*pen"thes\, n. [NL., fr. Gr. ?. See Nepenthe.]
   1. Same as Nepenthe. --Milton.
      [1913 Webster]

   2. (Bot.) A genus of climbing plants found in tropical areas
      of India, Malaya, Australia, etc., which have the leaves
      prolonged into a kind of stout tendril terminating in a
      pitcherlike appendage, whence the plants are often called
      pitcher plants and monkey-cups. There are about thirty
      species, of which the best known is Nepenthes
      distillatoria. See Pitcher plant.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Nepenthes
    n 1: pitcher plants [syn: Nepenthes, genus Nepenthes]