\Zyg`a*poph"y*sis\, n.; pl. {Zygapophyses}. [Gr. ? a yoke + E. apophysis.] (Anat.) One of the articular processes of a vertebra, of which there are usually four, two anterior and two posterior. See under {Vertebra}. -- {Zyg`ap*o*phys"i*al}, a.