schisto-

Fissure or split.

Greek skhizein, to split.

The tropical disease schistosomiasis, also called bilharzia, is caused by a parasitic worm of the Schistosoma genus (Greek sōma, body, so ‘divided body’), so called because the adults and young, schistosomes, are parasites on different organisms. Schism, a split or division between strongly opposed sections or parties, comes from the same Greek root, as does schist, a rock which can be split into thin irregular plates.