n. any of several human or animal diseases characterized by dark urine resulting from rapid breakdown of red blood cells; -- used especially of
blackwater fever, a severe form of malaria caused by the blood parasite Plasmodium falciparum. [ WordNet 1.5 +PJC ]

. Nebraska; -- a nickname alluding to the dark color of the water of its rivers, due to the presence of a black vegetable mold in the soil. [ Webster 1913 Suppl. ]