The word "most errable" implies the tendency to make mistakes frequently. Some antonyms for this word could be "impeccable," meaning faultless or flawless. Another antonym could be "infallible," meaning incapable of error or failure. "Accurate," "dependable," and "reliable" are also antonyms that could describe the opposite of someone who is most errable. These words suggest precision, trustworthiness, and consistency, whereas "most errable" implies carelessness, unreliability, and inconsistency. By using antonyms to describe the opposite of "most errable," we can convey positive traits of reliability and accuracy, which can be essential qualities in many situations, such as work or studying.