Archaic standalone noun; in modern Japanese, 下痢 (げり) is the standard word. This form survives mainly in medical or historical contexts and in compounds.
In old medical texts, the disease name 痢 often appears.
dysentery
diarrhea
children's dysentery; ekiri
dysentery
Archaic standalone kanji form for diarrhea; now mainly seen in compounds like 下痢.
The Chinese character 痢 is phono-semantic, combining 疒 “illness” with 利 as its phonetic element. It entered Japanese in words for dysentery and diarrhea and now occurs chiefly in compounds such as 下痢.