diarrhea (n.)
late 14c., from Old French diarrie, from Late Latin diarrhoea, from Greek diarrhoia "diarrhea" (coined by Hippocrates), literally "a flowing through," from diarrhein "to flow through," from dia- "through" (see dia-) + rhein "to flow" (see rheum). Respelled 16c. from diarria on Latin model.