ka-doink, boink
A sound you make when someone says something so dumb it’s like they’re talking to a wall. You might even make them eat a whole pie if they keep it up.
My brother said, 'I can’t believe I spilled my milk.' I boink-ed him and made him eat a whole pie.
My sister said, 'I can’t believe I wore my hat inside out.' I boink-ed her and gave her a time-out.
My dog said, 'I can’t believe I ate my hat.' I boink-ed him and made him do 10 sit-ups.