zenith
/ˈzenɪθ; `zinɪθ/ n
1 point in the heavens directly above an observer 天顶（观测者正上方的天空）. Cf 参看 nadir.
2 (fig 比喻) highest point (of power, prosperity, etc); peak （权力、 繁荣等的）最高点; 顶点
reach the zenith of one's career, power, influence 达到事业的、 权力的、 影响力的顶峰
At its zenith the Roman empire covered almost the whole of Europe. 罗马帝国的全盛时期几乎占据了整个欧洲.