Translation

介入する / 仲裁する / 間に入る

Meaning

Intervene means to step into a situation to help, stop harm, settle a dispute, or change the outcome. It is often neutral or positive; if the involvement is unwanted and troublesome, interfere is usually better.

Examples

• 警察はけんかが大きくなる前に介入しました。
  Police intervened before the fight got worse.
• 先生は二人の生徒の争いを仲裁しました。
  The teacher intervened in the dispute between two students.