[TA] a canal beginning at the opening of the internal acoustic meatus in the posterior cranial fossa, passing laterally through the petrous portion of the temporal bone to end at the fundus, where a thin plate of bone separates it from the vestibule; it gives passage to the facial and vestibulocochlear nerves together with the labyrinthine artery and veins. SYN: meatus acusticus internus [TA], internal auditory meatus.