Unflattering is a term used to describe something that is not attractive or complimentary. Antonyms for unflattering could include words like flattering, complimentary, attractive, appealing, or beautiful. These words describe something that is perceived in a positive way and shows the subject in a good light. Some other possible antonyms could include words like idealizing, exalting, ideal, or perfect. These words indicate a level of perfection or perfectionism that is both attractive and appealing. No matter what the antonym, it is clear that when something is not unflattering, it is seen in a far more positive light.