alisphenoidal,a.Phys.|ˌælɪsfiːˈnɔɪdəl| [f.prec. + -al1.] Pertaining to the wings of the sphenoid bone. 1849–52Todd Cycl.Anat. & Phys. IV. 1298/1 Alisphenoidal..air-cells.1866Huxley Preh. Rem. Caithn. 153 If alisphenoidal synostosis is the cause of the frontal depression of the Neanderthal skull.