purgative (adj.)youdaoicibaDictYouDict[purgative 词源字典]
late 14c., from Old French purgatif (14c.) and directly from Late Latin purgativus, from purgat-, past participle stem of Latin purgare (see purge (v.)). The noun is attested from early 15c. (Old English medical texts have clænsungdrenc).[purgative etymology, purgative origin, 英语词源]