petrosal

/P EH0 T R OW1 Z AH0 L/
noun
  1. 1

    A petrosal bone.

  2. 2

    The auditory capsule.

adjective
  1. 1

    Of great hardness; petrous.

  2. 2

    Of, pertaining to, or located near the petrous part of the temporal bone.

Source: https://en.wiktionary.org/wiki/petrosal