a series of cavities within the petrous portion of the temporal bone forming the vestibule, cochlea, and semicircular canals of the inner ear

the cavity in the skull which contains the inner ear mechanism.

The space in the skull where the inner ear resides.

cavity in the petrous part of the temporal bone that contains the membranous labyrinth

The cavity within the temporal bone of the skull which contains the inner-ear and balance system.