Origin of petrous
Examples from the Web for petrous
The bony labyrinth presents a series of cavities which are channelled through the substance of the petrous bone.
From the surrounding 794 mesoderm the petrous bone is formed by a process of chondrification and ossification.
By this means the posterior surface of the petrous bone can be exposed as far inwards as the internal auditory meatus.
The bones related to the organ of hearing, the tympanis and petrous bones, are very solid and dense in structure.The Cambridge Natural History, Vol X., Mammalia|Frank Evers Beddard
On its inner side is a small air chamber in the petrous portion of the temporal bone, called the cavity of the tympanum.A Practical Physiology|Albert F. Blaisdell
British Dictionary definitions for petrous
Word Origin for petrous
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].