[N-COUNT 可数名词](尤指带球形圆屋顶的)圆形建筑,圆形房间 A rotunda is a round building or room, especially one with a round bowl-shaped roof.
...the rotunda of the Hotel des Invalides in Paris.
巴黎荣军院的圆顶建筑
Oxford
ro·tunda/rəʊˈtʌndə; NAmEroʊˈtʌndə/noun _architecture_comp.jpg _rotunda.jpg a round building or hall, especially one with a curved roof (= a dome) 圆形建筑,圆形大厅(尤指带有圆顶的)rotundarotundasro·tunda/rəʊˈtʌndə; NAmEroʊˈtʌndə/