The word "unthriving" means not prospering or growing. However, there are many antonyms to this word, including thriving, flourishing, prospering, blooming, growing, thriving, successful, prosperous, and fruitful. These words describe a state of growth, prosperity, and progress. When we use these words, we describe a situation where things are not just stagnant or unchanging but are actually improving and growing. Such a situation could be in business or personal life. Whatever the context, it represents a more positive and productive outlook than the negative connotations associated with "unthriving.