The word "most chafing" refers to something that is particularly irritating or annoying. Its antonym would be something that is soothing or comforting. Words like calming, relaxing, pleasant, gentle, or easygoing could be used to describe the opposite of something that is most chafing. Moreover, one could use words like agreeable, enjoyable, sweet, or mild to explain something that is the antithesis of "most chafing." On the other hand, unpleasant, bothersome, disturbing, or vexatious can be used as synonyms of "most chafing." Finding the right antonym for "most chafing" will depend on the context in which it is being used.