際さいに

adverb

in case of; at that time; at this time

Used to indicate a specific occasion or situation when something happens. Often follows a noun or verb in dictionary form. Can refer to past, present, or future events depending on context.

• 地じ震しんの際さいには、まず身みの安あん全ぜんを確かく保ほしてください。

  In case of an earthquake, please ensure your safety first.

• お会あいした際さいに、その話はなしをしましょう。

  Let's talk about it when we meet.