The Collaborative International Dictionary of English v.0.48:

Suttee \Sut*tee"\, n. [Skr. sat[imac] a faithful wife, fem. of
   sant existing, real, true, good, p. pr. of as to be. Cf.
   Sooth.]
   1. A Hindoo widow who immolates herself, or is immolated, on
      the funeral pile of her husband; -- so called because this
      act of self-immolation is regarded as envincing excellence
      of wifely character. [India]
      [1913 Webster]

   2. The act of burning a widow on the funeral pile of her
      husband. [India]
      [1913 Webster]

   Note: The practice, though abolished in British India law in
         1829, is not wholly prevented.
         [1913 Webster]

WordNet (r) 3.0 (2006):

suttee
    n 1: the act of a Hindu widow willingly cremating herself on the
         funeral pyre of her dead husband