zygal,a.Anat.|ˈzaɪgəl| [f. zygon + -al1.] Pertaining to or having a zygon. 1886B. G. Wilder in Jrnl.Nerv. & Mental Dis. June 304 The complete or typical condition of a zygal fissure is like two y's joined by their stems,..or, viewed from the side, like an expanded H.