Self-opinionatedness refers to a person's tendency to cling to their own ideas and beliefs, often to the point of being closed-minded or obstinate. The antonyms for this word, therefore, would be traits that reflect openness, flexibility, and a willingness to consider other perspectives. Some good antonyms for self-opinionatedness might include things like open-mindedness, receptivity, humility, and willingness to learn. Additionally, other traits that might be considered antonyms for self-opinionatedness could include traits like acquiescence, compromise, and cooperation, all of which reflect a willingness to work with others and adapt to changing circumstances. Ultimately, the key to overcoming self-opinionatedness is to cultivate an attitude of openness and a willingness to learn and grow throughout your life.