back down

verb3

1. •
   To take a less aggressive position in a conflict than one previously had, or has planned to have.

   • I was about to sue them, but I had to back down.
   • The boys had planned to fight during recess, but backed down after the principal found out.
2. •
   To make (someone) take a less aggressive position.

   • I have backed down so many men by confronting them. I'm willing to fight back. If you have that rage in your heart and you are willing to kill, that radiates. — 1980
3. •
   To withdraw from a commitment or position; back out.