To keep quite on something. To not tell people about something. To not divulge information to people that should not know about something. Keeping certain information limited to a certain group or between two people.
A very violent act in which a person's mouth is open and placed on a curb of a road, sidewalk or any other raised surface slightly off of the ground. The person perpetrating the act then stomps on the back of the head of the victim causing massive injuries to the victim’s head and mouth.
"Don't fuck with him man. The last guy who fucked with him got a curbie!"