amphitheatre
noun [ C ] UK (US amphitheater) uk/ˈæm.fɪˌθɪə.tər/ us/ˈæm.fəˌθiː.ə.t̬ɚ/
（露天）圆形剧场（或竞技场）
a circular or oval area of ground around which rows of seats are arranged on a steep slope, for watching plays, sports, etc. outside
阶梯教室，看台式教室
a large hall for lectures in which the rows of seats are arranged on a slope