Throwing the towel is a phrase that refers to giving up or surrendering. There are several antonyms for this phrase, depending on the context of the situation. One possible antonym is perseverance or persistence, which means to keep going despite challenges or setbacks. Another antonym is resilience, which refers to the ability to recover quickly from difficult situations. Other antonyms include determination, tenacity, and grit, which all suggest a strong will and an unwillingness to give up. These opposite terms emphasize the importance of pushing through adversity and fighting to achieve one's goals, rather than giving up in defeat.