Being on a par with means being equal to someone or something else in terms of status or quality. The antonyms or opposite meanings of this phrase could be "inferior," "subordinate," "unequal," "inferiority," or "lower level." When someone or something is not on a par with others, it means that they do not have the same standard of quality or status as the others. Being on a par with is an expression used to compare individuals or things that are supposedly at the same level. The opposite expressions, therefore, suggest that there is a mismatch or difference between two entities.