Merriam-Webster Collegiate Dictionary - diarrhea

 noun  Etymology: Middle English diaria, from Late Latin diarrhoea, from Greek diarrhoia, from diarrhein to flow through, from dia- + rhein to flow — more at stream  Date: 14th century  1. abnormally frequent intestinal evacuations with more or less fluid stools  2. excessive flow verbal ~  • ~l adjective  • diarrheic adjective  • diarrhetic adjective DIARRHEAL  adjective see diarrhea