The word "facetiousnesses" refers to humor or wit that is meant to be amusing or amusingly inappropriate. Antonyms for this word could include seriousness, solemnity, gravity, or sobriety. These words all connote a lack of humor or lightheartedness in speech or behavior. Other antonyms for facetiousnesses might include sincerity, earnestness, or authenticity, as these words describe a genuine or heartfelt expression of beliefs or emotions, rather than the kind of playful banter or teasing that facetiousnesses implies. Whether we are talking about work or personal relationships, understanding antonyms for facetiousnesses can help us communicate more effectively and appropriately.