Source : Webster's Revised Unabridged Dictionary (1913)

Hypapophysis \Hy`pa*poph"y*sis\, n.; pl. {Hypapophyles}. [NL.
   See {Hypo-}, and {Apophysis}.] (Anat.)
   A process, or other element, of a vertebra developed from the
   ventral side of the centrum, as h[ae]mal spines, and chevron
   bones. -- {Hy`pa*po*phys"i*al}, a.