A severe form of malaria characterized by hemolysis and dark urine due to breakdown of red blood cells.

काली जल बुखार

English Usage: After traveling to the tropics, he was diagnosed with blackwater fever.

Hindi Usage: उष्णकटिबंधीय क्षेत्र में यात्रा के बाद, उसे काली जल बुखार का निदान किया गया।