nonevent /ˌnɒnɪˈvɛnt/

also non-event

• 1. 

  N-COUNT If you say that something was a nonevent, you mean that it was disappointing or dull, especially when this was not what you had expected. 令人失望的事; 令人扫兴的事

  例：

  Unfortunately, the entire evening was a total nonevent.

  很遗憾，整个晚上完全让人大失所望。