Bust someone’s chops

Chops meaning one’s jaw was Standard English in the early 1500s and then became low informal by the mid-17th century. To bust someone’s chops is American informal from the mid-19th century, meaning to strike or punch someone on the jaw. It then became figurative in the sense of criticising someone or giving them a hard time from the late 19th century. See also Lick one’s chops.