The antonyms for the word "most unpermissive" could be "most permissive" or "most lenient." These terms describe a situation or person that is more accepting, allowing freedom of actions or beliefs. In a permissive environment or with a permissive person, there is an open-minded and understanding attitude toward different ideas and behaviors. This approach encourages creativity, communication, and mutual respect. On the other hand, an unpermissive environment or person is rigid, strict, and intolerant of different ideas or approaches. Therefore, by being more permissive, we can create a more harmonious and inclusive society that values individuality and diversity.