\He"mal\, a. [Gr. a"i^ma blood.]
Relating to the blood or blood vessels; pertaining to,
situated in the region of, or on the side with, the heart and
great blood vessels; -- opposed to neural.
Note: As applied to vertebrates, hemal is the same as
      ventral, the heart and great blood vessels being on the
      ventral, and the central nervous system on the dorsal,
      side of the vertebral column.
{Hemal arch} (Anat.), the ventral arch in a segment of the
   spinal skeleton, formed by vertebral processes or ribs.