The word "most superexcellent" is an expression used to describe something that is extremely good or remarkable. However, when we look for antonyms, we can find words such as mediocre, ordinary, average, unsatisfactory, and inferior. Mediocre refers to something that is of average or low quality, while ordinary simply implies that it is not exceptional. Something that is average is neither good nor bad, just average. Unsatisfactory implies that it failed to meet our expectations, while inferior is a term that suggests something is of lesser quality. Therefore, when looking for antonyms for "most superexcellent," we can find words that connote the opposite of something that is exceptional or excellent.