A double chin refers to the accumulation of excess fat under the chin, creating the appearance of a second chin. This condition can be caused by various factors, including genetics, aging, weight gain, and loss of skin elasticity. As we age, the skin loses its firmness and the muscles weaken, contributing to the formation of a double chin. While it's a natural part of aging for many people, it can also be a result of lifestyle factors. Treatments often focus on targeting the excess fat and improving skin tone, with options ranging from targeted exercises to non-surgical procedures.