metapophyses

from The Collaborative International Dictionary of English v.0.48

Metapophysis \Met`a*poph"y*sis\, n.; pl. {Metapophyses}. [NL.
   See {Meta-}, and {Apophysis}.] (Anat.)
   A tubercle projecting from the anterior articular processes
   of some vertebrae; a mammillary process.
   [1913 Webster]