The word "ungenuine" means something that is false or not authentic. Its antonyms, on the other hand, are words that describe something genuine, true or authentic. Some of the antonyms for un-genuine are genuine, authentic, real, true, sincere, honest, trustworthy, reliable, and legitimate. A person who is genuine is honest, trustworthy and true to their words. Authenticity is a characteristic of something that is original, true and not fake. Using the right antonyms for the word "ungenuine" can help you to describe things or people that are reliable and true, making your communication clear and precise.