expression, godan verb (-tsu)
cut off the retreat; burn one's bridges
Idiomatic expression meaning to eliminate any possibility of escape or going back, often used figuratively for committing oneself fully to a course of action.
彼は退路を断って、新しい事業に挑戦した。
He burned his bridges and took on a new business venture.
退路を断つ
I made this decision with the resolve to cut off all retreat.