The Collaborative International Dictionary of English v.0.48:

Pitcher \Pitch"er\, n. [OE. picher, OF. pichier, OHG. pehhar,
   pehh[=a]ri; prob. of the same origin as E. beaker. Cf.
   Beaker.]
   1. A wide-mouthed, deep vessel for holding liquids, with a
      spout or protruding lip and a handle; a water jug or jar
      with a large ear or handle.
      [1913 Webster]

   2. (Bot.) A tubular or cuplike appendage or expansion of the
      leaves of certain plants.
      [1913 Webster]

   American pitcher plants, the species of Sarracenia. See
      Sarracenia.

   Australian pitcher plant, the Cephalotus follicularis, a
      low saxifragaceous herb having two kinds of radical
      leaves, some oblanceolate and entire, others transformed
      into little ovoid pitchers, longitudinally triple-winged
      and ciliated, the mouth covered with a lid shaped like a
      cockleshell.

   California pitcher plant, the Darlingtonia California.
      See Darlingtonia.

   Pitcher plant, any plant with the whole or a part of the
      leaves transformed into pitchers or cuplike organs,
      especially the species of Nepenthes. See Nepenthes.
      [1913 Webster]

WordNet (r) 3.0 (2006):

California pitcher plant
    n 1: marsh or bog herb having solitary pendulous yellow-green
         flowers and somewhat twisted pitchers with broad wings
         below [syn: California pitcher plant, Darlingtonia
         californica]