knock (people's) heads together

knock (people's) heads together

To scold two or more people harshly. If you two do something this stupid again, I'm going to knock your heads together!
See also: head, knock, together

knock people's heads together

or

bang people's heads together

mainly BRITISH, INFORMAL
If you knock people's heads together or bang their heads together, you forcefully make them stop arguing. If he's unable to knock everybody's heads together, then questions are going to be raised about his own ability to continue in office. The idea is to bang their heads together until they come out with a sensible deal. Note: You can also say that someone bangs heads together or knocks heads together. Chris Smith said he would bang heads together.
See also: head, knock, together

bang/knock your/their ˈheads together

(informal) force people to stop arguing and behave in a sensible way: I’d like to bang those stupid politicians’ heads together.
See also: bang, head, knock, together