The word "most nonbeliever" implies a sense of disbelief or skepticism towards something. Its antonyms would be words that express belief, faith, or trust in something. Some antonyms for "most nonbeliever" could be devout, faithful, believer, follower, or supporter. These words suggest an unwavering commitment to a particular belief or value system. In contrast to "most nonbeliever," they conjure up feelings of confidence, conviction, and assurance. People who identify as devout, faithful, or followers have a strong sense of purpose and direction, and they are often motivated by a sense of inner conviction that drives them forward.