knock someone's block off
US /nɑk ˈsʌm.wʌnz blɑk ɔf/
UK /nɑk ˈsʌm.wʌnz blɑk ɔf/
1.
to hit someone very hard, especially in the head or face, often as a threat or in anger
:
•
If you don't stop bothering me, I'm going to knock your block off!
•
He was so angry, he threatened to knock the guy's block off.