The antonyms for the word "un permissible" are permissible, allowed, approved, authorized, legal, legitimate, lawful, licit, acceptable, and sanctioned. These words are used to describe actions, behaviors, and decisions that are in accordance with the law, rules, or norms. The opposite of un permissible means that the action or behavior is acceptable, lawful, and within the boundaries of what is allowed or approved. Antonyms are useful in creating clear and concise communication, providing context to the conversation, and avoiding ambiguity. In conclusion, it's important to understand the antonyms of un permissible to communicate more effectively while avoiding confusion.