The phrase "marching to a different drummer" means to behave or act in a way that is different from the norm. Antonyms for this phrase would include conformity, compliance, and adherence. Conformity implies following the crowd and accepting societal norms without question. Compliance suggests obeying rules or regulations without deviation. Adherence denotes strict adherence to a particular doctrine or ideology. These antonyms emphasize the importance of conforming to established social norms, rules, and values, rather than deviating from them. While marching to a different drummer may sometimes be necessary for creativity, innovation, and progress, it can also lead to isolation, rejection, and misunderstandings.