superstructure

n. /ˈsuːpərstrʌktʃər/ C2

上层建筑；地上结构

The structure built on top of something else.

仙境例句

The sea school had a strange superstructure of shells built on top of an old rock.

海底学校建在一块老岩石上，岩石上面是用贝壳搭起来的奇怪上部结构。