Antonyms for the word "jokiest" would be serious, solemn, sincere, grave, or earnest. Jokiest describes someone or something that is humorous, funny, or comical. Its antonyms are words that describe the opposite of these characteristics. Serious implies a lack of humor or levity, while solemn connotes a grave or solemn mood or behavior. Sincere means genuine, honest, or truthful, while grave describes the seriousness or solemnity of a situation or demeanor. Earnest suggests a serious and enthusiastic approach to something. These antonyms provide a range of words to describe something that is not jokiest, conveying a more serious, solemn, and sincere tone.