a. Anat. Also 8 sphænoidal, 89 sphenoïdal. [ad. mod.L. sphēnoidālis († sphæn-), f. sphēnoidēs SPHENOID. So F. sphénoïdal (18th cent.).]
1. Sphenoidal bone, the sphenoid bone.
1726. Monro, Anat., 88. It is connected to the sphenoidal Bone, by means of that same Suture.
1746. Phil. Trans., XLIV. 11. The Hole of the sphænoidal Bone, thro which the Optic Nerve passes.
1834. H. MMurtrie, Cuviers Anim. Kingd., 173. A narrow canal which traverses the palatine and sphenoidal bones.
2. Of or pertaining to, connected with, the sphenoid bone.
Chiefly in a number of special collocations, as sphenoidal angle, fissure, sinus, suture, etc.
1726. Monro, Anat., 88. The sphenoidal Suture connects it to the Wedge-like Bone.
1728. Chambers, Cycl., Sphenoidal Suture, in Anatomy, a Suture thus calld from its encompassing the Os sphenoides.
1808. Barclay, Muscular Motions, 505. The frontal, sphenoidal, and maxillary antres.
1822. J. Parkinson, Outl. Oryctol., 284. The sphenoidal plates which form a vault over the palate bones.
1854. R. Owen, in Orrs Circ. Sci., Org. Nature, I. 167. Such cells are called sphenoidal and ethmoidal sinuses in man.
1872. Mivart, Anat., 83. A long but narrow space, termed the sphenoidal fissure.