背はい約やく

noun, noun or participle which takes 'suru', intransitive verb

broken promise; breach of promise; breaking one's word

Refers to the act of breaking a promise or going back on one's word. Often used in formal or written contexts.

• 彼かれは背はい約やくをして、私わたしを裏うら切ぎった。

  He broke his promise and betrayed me.

• 契けい約やくの背はい約やくは許ゆるされない。