Also called African sleeping sickness, African trypanosomiasis. a generally fatal disease, common in parts of Africa, characterized by fever, wasting, and progressive lethargy: caused by a parasitic protozoan, Trypanosoma gambiense or T. rhodesiense, that is carried by a tsetse fly, Glossina palpalis.
2. Also called epidemic encephalitis, lethargic encephalitis.
a viral disease affecting the brain, characterized by apathy, sleepiness, extreme muscular weakness, and impairment of vision
Also, British, sleepy sickness.