Each vertebra (from the Latin vertere, meaning “something to turn on”) consists of a vertebral body, a vertebral arch, and articular processes. The vertebral body is the thick, disc-shaped, front portion of the vertebra that is weight-bearing. The vertebral arch extends backwards from the body of the vertebra. Each vertebral arch has lateral walls called pedicles (from the Latin pedicle, meaning “little feet”) and a roof formed by flat layers called laminae (from the Latin, meaning “thin plates”). The spinal cord passes through the area between the vertebral arch and the vertebral body. Seven vertebral processes (bony projections) extend from the lamina of a vertebra. Some of the processes are attachment sites for muscles. The other four processes form joints with other vertebrae above or below. Intervertebral discs separate each vertebra.