1. The vomiting of blood, typically caused by bleeding in the upper digestive tract.
Usage: medical term; also spelled hematemesis in some contexts; British spelling; American English often uses 'hematemesis'
2. Black or dark tarry stools resulting from bleeding in the upper or middle digestive tract.
Usage: medical term; from Greek melas (black) + haima (blood)

Examples

• The patient presented with melaena and abdominal pain.
• Melaena can indicate a serious gastrointestinal bleed requiring immediate medical attention.
• The doctor noted signs of melaena in the patient's medical history.
• Upper endoscopy was performed to investigate the cause of melaena.
• Melaena and hematemesis are both warning signs of internal bleeding.