1. To stop focusing on, thinking about, or obsessing over something. You should put those bad memories behind you and start focusing on the good life you have now. Let's just put this loss behind us and start preparing for the next game.

2. To provide or give something that aids, supports, or assists someone or something. The committee members promised to put the fund behind a development scheme for the impoverished area. We're putting all of our resources behind you and your team.