台だい無なしになる

expression, godan verb (-ru)

be ruined; be spoiled; come to nothing

Describes plans, efforts, moods, or things being completely ruined or wasted. Often used when something good is destroyed by a single event or mistake.

• 雨あめでせっかくのピクニックが台だい無なしになった。

  The long-awaited picnic was ruined by the rain.

• 彼かれの一ひと言ことで楽たのしい雰ふん囲い気きが台だい無なしになった。

  One word from him spoiled the pleasant atmosphere.