petrous
adjective
- of or like rock; hard; stony
- designating or of that part of the temporal bone which surrounds and protects the internal ear
See petrous in American Heritage Dictionary 4
(pĕtˈrəs)
adjective- Of, relating to, or resembling rock, especially in hardness; stony.
- Of or relating to the very dense, hard portion of the temporal bone that forms a protective case for the inner ear.
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