Untrueness, as its name suggests, means something that is not true or false. Its antonyms include words like truthfulness, veracity, honesty, sincerity, authenticity, accuracy, and reliability, which refer to attributes or qualities of being true or genuine. Truthfulness is the direct opposite of untrueness and refers to the quality of being truthful or honest in one's thoughts, words, and deeds. Veracity also means the quality of being truthful and accurately stating facts. Honesty refers to the quality of being sincere and truthful in one's dealings with others. Authenticity implies being genuine, reliable, and transparent in one's actions and behavior. Accuracy refers to the quality of being precise and exact, and reliability suggests trustworthiness and dependability in one's assertions or commitments.