Laugh lines, also known as smile lines or character lines, refer to the wrinkles or creases that appear around the corners of the mouth and eyes when a person smiles or laughs. Some other synonyms for laugh lines include crow's feet, happy lines, joy lines, laughter lines, and crinkle lines. Crow's feet tend to appear around the eyes and are more noticeable when a person smiles. Happy lines or joy lines are considered a more positive and uplifting term for laugh lines. Laughter lines and crinkle lines may also be used to describe these wrinkles. Overall, laugh lines are a natural part of aging and can be seen as a sign of a happy and fulfilling life.