COMMON If someone beats their breast or beats their chest, they publicly show regret or anger about something that has happened. At this month's meeting of the party's Central Committee, the party leader beat his breast with ritual self-criticism. Why don't you both stop beating your chests and do something productive? Note: You can describe the action of doing this as breast-beating or chest-beating. His breast-beating on behalf of the working classes always seemed false to me. Note: You usually use these expressions to suggest that the person is not being sincere but is trying to draw attention to himself or herself.