Merriam-Webster Collegiate Dictionary - trypanosome

 noun  Etymology: New Latin Trypanosoma, from Greek trypanon auger + New Latin -soma -some — more at trepan  Date: 1903 any of a genus (Trypanosoma) of parasitic flagellate protozoans that infest the blood of various vertebrates including humans, are usually transmitted by the bite of an insect, and include some that cause serious diseases (as sleeping sickness and Chagas' disease)