The word "untruer" is a double negative, which means it is not a word. However, the word "true" has many antonyms that can be used in its place to convey the opposite meaning. Some common antonyms for the word "true" include false, fake, untrue, fabricated, fictitious, incorrect, misleading, and wrong. These words represent the opposite of truth and often indicate dishonesty or inaccuracies. When choosing antonyms for the word "true," it is important to consider the context and intended meaning to ensure the appropriate word is selected. By using antonyms effectively, you can convey a variety of ideas and create a more nuanced understanding of a topic.