The bone in the neck that supports the head is the atlas, also called the first cervical vertebra or C1. It sits at the top of the spinal column, directly beneath the skull, and forms a joint with the occipital bone.
The atlas is unusual because it is a ring-shaped vertebra without a typical vertebral body. Its broad lateral masses support the skull, while the atlanto-occipital joints allow the head to tilt forward and backward—the movement associated with nodding “yes.”
The atlas works with the axis, or C2, the vertebra immediately below it. The axis has a tooth-like projection called the dens, which acts as a pivot so the atlas and head can rotate from side to side. This is why the upper two cervical vertebrae are specially shaped for head movement.
The name comes from Atlas, the figure in Greek mythology associated with bearing a great weight. A common mix-up is choosing the scapula or clavicle: both are shoulder bones, while the sternum is the breastbone. The atlas is specifically the neck vertebra that meets the skull and helps carry and move the head.