The Collaborative International Dictionary of English v.0.48:

Melena \Me*le"na\, n. (Med.)
   See Melaena.
   [1913 Webster]

WordNet (r) 3.0 (2006):

melena
    n 1: abnormally dark tarry feces containing blood (usually from
         gastrointestinal bleeding) [syn: melena, melaena]