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1. Of, relating to, or resembling rock, especially in hardness; stony.
2. Of or relating to the very dense, hard portion of the temporal bone that forms a protective case for the inner ear.

[Middle English, from Old French petros, from Latin petrōsus, rocky, from petra, rock, from Greek petrā; see per- in Indo-European roots.]


(ˈpɛtrəs; ˈpiː-)
1. (Anatomy) anatomy denoting the dense part of the temporal bone that surrounds the inner ear
2. rare like rock or stone
[C16: from Latin petrōsus full of rocks]


(ˈpɛ trəs, ˈpi-)

like stone, esp. in hardness; stony; rocky.
[1350–1400; Middle English (< Middle French petros) < Latin petrōsus rocky.]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.petrous - (of bone especially the temporal bone) resembling stone in hardness
hard - resisting weight or pressure
References in periodicals archive ?
According to our study, the superior and inferior length of IAM were about one fifth and one sixth of the length of petrous bone, respectively.
Because of streak artifacts from the petrous bone, CT is usually unable to detect these changes.
Adam Petrous and Karel Rada found to their cost as Bowyer went biting into tackles all over the pitch.
Radiologically the erosion of the petrous apex and erosion of foramen ovale, rotendum, superior orbital fissure and displacement of the internal carotid artery are characteristic and have diagnostic value.
One possible cause is a cholesteatoma of the middle ear or petrous bone.
Complications of CSOM are broadly classified into intratemporal (Coalescent mastoidoitis, facial nerve palsy, labyrinthitis and petrous apicitis) and intracranial complications (Meningitis, Extradural abscess, Subdural abscess, Brain abscess, Sigmoid sinus thrombosis and Otitic hydrocephalus).
Preoperative computed tomography demonstrated an unusually distended bony canal that passed through the superolateral portion of the right petrous bone.
There was a menace about his game that had been missing - as Adam Petrous and Karel Rada found to their cost as he went biting into tackles all over the pitch.
They occur less frequently within the occipital, temporal, sphenoid, and petrous bones.
High-resolution computed tomography (CT) of the patient's petrous bones elucidated abnormal soft-tissue density in the left middle ear cavity, with bony destruction (figure 1).
Drilling of the petrous bone will often open up mastoid air cells, which communicate with the middle ear cavity.
Facial paralysis in a patient with cholesterol cyst of the petrous bone.