metropolis
n.
"seat of a metropolitan bishop," 1530s, from Late Latin metropolis; see metropolitan. Meaning "chief town or capital city of a province" is first attested 1580s, earlier metropol (late 14c.).
〔李〕[metro-;polis] n.主要都市； 中心城市 ←polis,polit (GK polis,politeia)=(government of) city 城市（治理）
〔蒋〕[metra母，polis城市;’母城”→首城，最大的城] 大城市，主要城市，大都会，首府
〔蒋〕[metro母→主要的，polis城;’母城”→主要的城] 大城市，大都会，首府