Excessive and frequent evacuation of watery feces.
[Middle English diaria, from Medieval Latin, from Late Latin diarrhoea, from Greek diarroia, from diarrein, to flow through : dia-, dia- + rhein, to flow, run; see sreu- in the Appendix of Indo-European roots.]
di′ar·rheal, di′ar·rheic (-ĭk), di′ar·rhetic (-rĕtĭk) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.