Super duper is an informal phrase that means excellent, outstanding or amazing. The word duper is derived from the French word "dupe" which means someone easily deceived. But there are certainly people who are not wowed by things that are super duper. In fact, there are many antonyms for this word which include awful, terrible, boring, and ordinary. The opposite of super duper would be something that is simply average, mediocre, or unsatisfactory. Therefore, the choice of words used to describe something often depends on one's perspective and what they consider good or bad.