a tropical infectious disease caused by the protozoan Leishmania donovani in the liver, spleen, etc, characterized by fever and weight loss; visceral leishmaniasis
Word origin
from Assamese kālā black + āzār disease
kala azar in American English
(ˌkɑlɑɑˈzɑr)
an infectious disease, a type of leishmaniasis, that occurs in subtropical or tropical areas, caused by a protozoan parasite (Leishmania donovani) transmitted by sand flies (esp. genus Phlebotomus), and characterized by an enlarged spleen and liver, irregular fever, anemia, etc.