esplanade
/ˌespləˈneɪd/noun
1- a long, open, level area, typically beside the sea, along which people may walk for pleasure（尤指海滨供散步用的）大道, 广场。
1.1
- an open, level space separating a fortress from a town（要塞与城镇间的）旷地。
词源
late 16th cent. (denoting an area of flat ground on top of a rampart)： from French, from Italian spianata, from Latin explanatus 'flattened, levelled', from explanare （see EXPLAIN）.