英语词源字典 - 在线词源网站

cholera (n.)[cholera 词源字典]: late 14c., "bile, melancholy" (originally the same as choler), from Middle French cholera or directly from Late Latin cholera, from Greek kholera "a type of disease characterized by diarrhea, supposedly caused by choler" (Celsus), from khole "gall, bile," from khloazein "to be green," from khloros (see Chloe). But another sense of khole was "drainpipe, gutter."

Revived 1560s in classical sense as a name for a severe digestive disorder (rarely fatal to adults); and 1704 (especially as cholera morbus), for a highly lethal disease endemic in India, periodically breaking out in global epidemics, especially that reaching Britain and America in the early 1830s.[cholera etymology, cholera origin, 英语词源]
epidemiology (n.): "study of epidemics, science of epidemic diseases," 1850, from Greek epidemios, literally "among the people, of one's countrymen at home" (see epidemic) + -logy. Related: Epidemiological; epidemiologist.