The opposite of unmistakability is ambiguity, which refers to unclear or uncertain meaning, causing confusion or doubt. Another antonym of unmistakability is indistinctness, meaning a lack of clarity or visible distinction. Vagueness is another antonym, referring to an obscure, imprecise or uncertain quality or attribute. Obscurity, murkiness, and haziness are other antonyms for unmistakability and are used to describe something that is not clear, precise, or distinct. These words suggest a lack of clearness, which can result in confusion, misinterpretation, or misunderstanding. Overall these antonyms highlight the importance of clarity, precision, and discernibility in our communication and interactions with others.