Translation

偶然の一致 / 偶然 / 巡り合わせ

Meaning

A coincidence is a surprising match or connection between events that happens by chance, without planning or a clear cause. It does not prove that one event caused the other.

Examples

• 私たちが同じ日に同じ本を買ったのは偶然でした。
  It was a coincidence that we bought the same book on the same day.
• 彼に空港で会ったのはまったくの偶然でした。
  Meeting him at the airport was a complete coincidence.