megalopolis (n.)youdaoicibaDictYouDict[megalopolis 词源字典]
1832, from comb. form of Greek megas (genitive megalou) "great" (see mickle) + polis "city" (see polis). The word was used in classical times as an epithet of great cities (Athens, Syracuse, Alexandria), and it also was the name of a former city in Arcadia.[megalopolis etymology, megalopolis origin, 英语词源]