The jawline is primarily defined by the mandible, which is the largest bone in the human skull. This bone forms the lower jaw and contributes to the shape of the lower third of the face. While jaw muscles play a role in the appearance of the jawline, the underlying structure is primarily bone.
For example, jaw surgery, also known as genioplasty or mentoplasty, reshapes the chin by either adding an implant or reducing the bone itself to achieve a desired jawline.
However, it's important to note that the jawline can be influenced by other factors like muscle definition, skin elasticity, and even weight fluctuations.
In summary, while the jawline is not exclusively made of bone, the mandible is the primary bone that shapes and defines it.
