Antonyms for the word "most super-excellent" can be tricky to pinpoint, as it's a very strong superlative statement. However, some possible opposite terms could be "mediocre", "average", "inferior", or "unsatisfactory". While these words may seem harsh, they do provide a clear contrast to the extreme positivity conveyed by "most super-excellent". It's important to remember that language is all about context, and sometimes the negative connotations of antonyms can be valuable in helping to tone down unnecessary hyperbole. Regardless of the specific opposite term used, exploring antonyms is a useful way to gain a more nuanced understanding of the original word.