Definition of melena in US English:


(British melaena)


  • 1Dark sticky feces containing partly digested blood.

    • ‘Stools are examined for melena (ie, dark tarry stools) and occult blood.’
    • ‘In colon cancer, melena or maroon-colored stools tend to be a symptom of tumors in the ascending or transverse colon.’
    • ‘A fecal occult blood test can be administered to rule out false melena.’
    • ‘Hematemesis (ie, vomiting blood) or melena (ie, blood in the stool) rarely is noted but may present clinically due to esophagitis.’
    • ‘There was no history of fever, diarrhea, constipation, melena, hematochezia or urinary symptoms.’
    1. 1.1 The production of melena, following internal bleeding or the swallowing of blood.
      • ‘It is normal to lose 0.5 to 1.5 ml of blood daily in the gastrointestinal tract, and melena usually is identified when more than 150 ml of blood are lost in the upper gastrointestinal tract.’
      • ‘Unless colon cancer has metastasized to the liver, symptoms tend to be one or more of the following: hematochezia, melena, anemia resulting from occult blood loss and change in bowel habits.’
      • ‘One patient developed melena the day after admission, but no other bleeding was observed.’
      • ‘At external examination, blood smears on the body surface resulting from hematemesis or melena were present in 40 cases.’
      • ‘Mr A's past medical history is significant for gastrointestinal bleeding, although, currently, he denies nausea, vomiting, abdominal pain, constipation, diarrhea, or melena.’


Early 19th century: modern Latin, from Greek melaina, feminine of melas ‘black’.