pleonyoudaoicibaDictYouDict[pleon 词源字典]
"The posterior division of the body of a crustacean; the crustacean abdomen", Mid 19th cent. From ancient Greek πλέων, present participle of πλεῖν to swim, to sail from the same Indo-European base as Sanskrit plavate he floats, swims, Old Church Slavonic plavati, Russian plavat′ to swim.[pleon etymology, pleon origin, 英语词源]