1.NounA projecting lamina of bone on the inferior surface of the petrous portion of the temporal bone that is continuous with the tympanic plate and surrounds the base of the styloid process.
2.NounAn outpouching of peritoneum through the inguinal canal, from which the serous membrane (tunica vaginalis) covering the testicle is derived.
3.NounEither of a pair of projecting plates on the inferior surface of the sphenoid bone which articulate with the alae of the vomer.