Petrosal

(pet-rot -ml). Pertaining to the petrous portion of the temporal bone. As a noun, the petrous portion of the temporal bone itself. P. Bone, in biology, one of several portions of the temporal bone in the human fetus and in other animals. P. Nerves. See Nei-ves, Table of. P. Sinus, a name given to two venous sinuses, superior and inferior. The former is situated along the superior border of the petrous portion of the temporal bone; the latter, near the posterior border. P. Vein. Same as P. Sinus.