behind someone's back
This page is about the idiom behind someone's back
If you do something behind someone's back, you do it without letting them know about it.
- We've taught our kids that it's impolite to talk about people behind their backs.
- The nurses had to go behind the doctor's back when they reported him for drinking alcohol before doing operations.
When the player spoke with another team about playing for them, he did it behind his own team's back because
Contributor: Matt Errey