\Spi"nal\, a. [L. spinalis, fr. spina the spine: cf. F.
spinal. See {Spine}.]
1. (Anat.) Of, pertaining to, or in the region of, the
   backbone, or vertebral column; rachidian; vertebral.
2. Of or pertaining to a spine or spines.
{Spinal accessory nerves}, the eleventh pair of cranial
   nerves in the higher vertebrates. They originate from the
   spinal cord and pass forward into the skull, from which
   they emerge in company with the pneumogastrics.
{Spinal column}, the backbone, or connected series or
   vertebr[ae] which forms the axis of the vertebrate
   skeleton; the spine; rachis; vertebral column.
{Spinal cord}, the great nervous cord extending backward from
   the brain along the dorsal side of the spinal column of a
   vertebrate animal, and usually terminating in a threadlike
   appendage called the filum terminale; the spinal, or
   vertebral, marrow; the myelon. The nervous tissue consists
   of nerve fibers and nerve cells, the latter being confined
   to the so-called gray matter of the central portions of
   the cord, while the peripheral white matter is composed of
   nerve fibers only. The center of the cord is traversed by
   a slender canal connecting with the ventricles of the
   brain.