Basically, means to just for the person to stop everything he/she is doing and find the nearest gun, point it under their chin and pull the trigger . That way they will no longer bother you and you can get some peace and quiet without their pure bullshit spewing from their mouths. If one continues you to harass you after you say this, you legally have the right to make them discover what your fist tastes like. They cannot sue you for any reason.