The phrase "coming to naught" typically refers to a situation or effort that has failed or produced no meaningful result. Antonyms for this phrase would include terms such as "successful," "fruitful," "productive," and "effective." In contrast to coming to naught, these words describe outcomes where effort has led to a positive outcome or a desired goal has been achieved. Other useful antonyms for the phrase might include terms such as "triumphant," "outstanding," "flourishing," and "thriving," all of which suggest a state of success or accomplishment rather than disappointment or failure.