lemming (n.)youdaoicibaDictYouDict[lemming 词源字典]
small arctic rodent, c. 1600, from Norwegian lemming, from Old Norse lomundr "lemming." Perhaps from Lapp luomek. Figurative sense (in reference to their mass migrations that sometimes end in plunges into the sea) is from 1958.[lemming etymology, lemming origin, 英语词源]