that's it
That's the end of that; I've had enough of that. That's it, everyone, thank you for listening. There are refreshments in the other room. That's it! I can't listen to you two fighting anymore, I'm getting out of here!
That's it!
1. Inf. That does it!; That's the last straw! That's it! I'm leaving! I've had enough! Okay. That's it! I'm going to report you to human resources!
2. That is the answer! That's it! You are right. That's it! You got the right answer.