Guffawing is a term used to describe a loud and unrestrained burst of laughter. Its antonyms are sad, solemn, serious, and mournful. When someone is not guffawing, they may be experiencing a range of emotions from sadness to solemnity. Sadness is an overwhelmingly heavy feeling, and it is marked by feelings of despair, hopelessness, and grief. Solitude is a state of being alone, and it is usually associated with introspection and reflection. Seriousness is a sense of gravitas, an acknowledgment of the importance of the circumstances we find ourselves in. Finally, mournfulness is the expressing of grief or sorrow for someone who has passed on.