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Affixes

-rrhoea

Also ‑rrhoeic, and ‑rrhoeal (US ‑rrhea, ‑rhea, ‑rrheic, and ‑rrheal).

Discharge; flow.

Greek rhoia, flow, flux.

Diarrhoea (Greek dia, through) is a condition in which faeces are discharged from the bowels frequently and in a liquid form; gonorrhoea (Greek gonos, semen) is a venereal disease involving inflammatory discharge from the urethra or vagina; amenorrhoea (Greek a‑, without, plus mēn, month) is an abnormal absence of menstruation; seborrhoea is excessive discharge of sebum from the sebaceous glands.

The standard US spelling of the ending is ‑rrhea (diarrhea, seborrhea); it is occasionally spelled with only one r (diarhea, amenorhea).

Adjectives are formed in ‑rrhoeic (seborrhoeic, diarrhoeic), or ‑rrhoeal (gonorrhoeal, amenorrhoeal).