Which bone of the head is connected to the rest of the skull by a moveable synovial joint?

The mandible, or lower jawbone, is the only bone of the head that is connected to the rest of the skull by a movable synovial joint, specifically the temporomandibular joint (TMJ). This joint allows for a range of movements, including opening and closing the mouth as well as some sliding motion, which is essential for activities such as chewing and speaking.

The other bones listed do not have movable joints: the maxilla and frontal bone are immovable parts of the skull that contribute to its structure, while the temporal bone is also anchored in place and acts as a protective casing for the brain and the structures of the inner ear. The unique joint structure of the mandible allows for greater functionality compared to these other skull bones, making it essential for various activities involving mastication and vocalization.