The antonyms for the word "most fretting" are calm, happy, content, composed, tranquil, serene, cool, collected, assured, and peaceful. The term "fretting" typically describes a state of anxiety, annoyance, worry, or distress. Therefore, its antonyms are used to express the opposite emotions and feelings, such as relaxation, positivity, satisfaction, confidence, and tranquility. By using these antonyms in writing or conversation, you can effectively convey the opposite meaning of "most fretting." For instance, instead of saying, "I'm most fretting about the presentation," you could say, "I'm feeling calm and prepared for the presentation.