[pe-truh s, pee-]


Anatomy. noting or pertaining to the hard dense portion of the temporal bone, containing the internal auditory organs; petrosal.
like stone, especially in hardness; stony; rocky.

Origin of petrous

1350–1400; Middle English (< Middle French petros) < Latin petrōsus rocky. See petr-, -ous
Related formssu·per·pet·rous, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for petrous

Historical Examples of petrous

British Dictionary definitions for petrous



anatomy denoting the dense part of the temporal bone that surrounds the inner ear
rare like rock or stone

Word Origin for petrous

C16: from Latin petrōsus full of rocks
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

Word Origin and History for petrous

1540s, from Middle French petreux, from Latin petrosus "stony," from petra "rock," from Greek petra "rock, cliff, ledge, shelf of rock, rocky ridge," of uncertain origin. Possibly from PIE root *per- "to lead, pass over," if the original meaning is "bedrock" and the notion is "what one comes through to" [Watkins].

Online Etymology Dictionary, © 2010 Douglas Harper

petrous in Medicine




Of stony hardness.
Of or relating to the dense hard portion of the temporal bone that forms a protective case for the inner ear.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.