"Most shuddersome" refers to something that is extremely frightening, terrifying, or disturbing. Antonyms of this word would be terms that indicate a lack of fear, horror, or apprehension. For example, some antonyms of "most shuddersome" could be "comforting," "reassuring," "soothing," "pleasant," "delightful," "adorable," or "enchanting." Using antonyms to describe something can help to contrast the feeling that the original word conveys, making it easier to understand the context and tone of a piece of writing. Antonyms also provide a way to diversify vocabulary and create more nuanced descriptions of emotions and experiences.