nadir
/ˈneɪdɪə(r); ?@ ˈneɪdər; `nedɚ/ n
1 point in the heavens directly beneath an observer 天底. Cf 参看 zenith.
2 (fig 比喻) lowest point; time of greatest depression, despair, etc 最低点; 最压抑、 消沉等的时刻
This failure was the nadir of her career. 这次失败是她事业上的低