The phrase "dust someone's britches" is a colloquialism used to describe spanking or physically disciplining someone. Antonyms for this phrase would include terms related to praise, reward, and positive reinforcement. Some possible antonyms could include "commend," "praise," "reward," "prize," "applaud," "acknowledge," "encourage," "support," and "validate." These words convey the opposite meaning of physically chastening someone, instead focusing on acknowledging and rewarding positive behavior. It's important to consider these antonyms in our daily interactions and parenting, as positive reinforcement can often be a more effective tool for behavior modification than physical punishment.