The term substandard is often used to indicate poor quality or inferiority. The antonyms for this word can be excellent, superior, exceptional, first-rate, top-notch, outstanding, or premium. These words imply a level of quality that is beyond the average standard. Some other antonyms for the word substandard include top-quality, high-grade, top-of-the-line, and best-in-class. These are all terms that can be used to describe products, services or experiences that are of the highest quality, meeting or exceeding expectations. When seeking an antonym for substandard, it is important to focus on words that convey a sense of superiority, rather than simply the absence of inferiority.