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Synonyms

petrous

American  
[pe-truhs, pee-] / ˈpɛ trəs, ˈpi- /

adjective

  1. Anatomy. noting or pertaining to the hard dense portion of the temporal bone, containing the internal auditory organs; petrosal.

  2. like stone, especially in hardness; stony; rocky.


petrous British  
/ ˈpiː-, ˈpɛtrəs /

adjective

  1. anatomy denoting the dense part of the temporal bone that surrounds the inner ear

  2. rare like rock or stone

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • superpetrous adjective

Etymology

Origin of petrous

1350–1400; Middle English (< Middle French petros ) < Latin petrōsus rocky. See petr-, -ous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To investigate further, scientists extracted ancient DNA from the petrous portion of the temporal bone in both skeletons, an area known for preserving genetic material.

From Science Daily • Feb. 17, 2026

Researchers targeted DNA stored in the petrous, a very dense bone that envelopes the inner ear.

From New York Times • May 26, 2022

The researchers located ancient DNA in their petrous bones—dense inner ear bones that preserve genetic material particularly well—but only managed to successfully retrieve a complete genome from the man.

From Science Magazine • May 26, 2022

Then, sifting through several large pieces of skull, he finds both petrous bones — dense nuggets behind the ear that preserve DNA better than other parts of the skeleton or the teeth.

From Nature • Sep. 18, 2016

It is bounded externally by the membrana tympani; internally by its inner wall; and in its circumference by the petrous portion of the temporal 416 bone and mastoid cells.

From A Treatise on Anatomy, Physiology, and Hygiene (Revised Edition) by Cutter, Calvin