Dientamoeba fragilis is a single celle parasite that infects the gastrointestinal tract of humans. Trophozoites of D. fragilis characteristically have two nuclei, hence the 'DI' prefix to the genus name. However, the rest of the genus name indicates that it is an ENTeric AMOEBA and not that it is related to intestinal parasites of the genus Entamoeba. The species name refers to the fact that the trophozoite stages are fragile - they do not survive long in the stool after leaving the body of the human host.