the series of joined vertebrae forming the axial support for the skeleton; spine; backbone
See spinal column in American Heritage Dictionary 4
noun
The series of articulated vertebrae, separated by intervertebral disks and held together by muscles and tendons, that extends from the cranium to the coccyx or the end of the tail, encasing the spinal cord and forming the supporting axis of the body; the spine. Also called vertebral column.
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spinal column
right lateral view of an adult human spinal column