Liberal Dictionary English Dictionary
n.
- A muscle with origin from the transverse processes of the lower thoracic vertebrae, with insertion into the ribs between the angles and tubercles, and into the transverse processes of the upper lumbar vertebrae, by medial slips into the accessory processes of the upper lumbar vertebrae and into the transverse processes of the thoracic vertebrae, with nerve supply from the dorsal branches of the thoracic and the lumbar nerves, and whose action extends the vertebral column.