Petrous

Part of speech: adjective

Definitions

1. Referring to the dense and bony section of the skull that houses the inner ear structures, it is also noted for its hard, rock-like quality and geological associations
2. It describes the tough, stony portion of the temporal bone that contains the inner ear anatomy, frequently noted for its solid texture in both anatomical and geological references
3. Pertaining to a solid, dense bone in the skull that encloses the inner ear ; having characteristics similar to stone or rock in texture or composition

Etymology: Ancient Greeks called a rock "pétra," and that single word sits behind the anatomical term "petrous." The Romans borrowed it as "petra" and built "petrōsus," meaning "full of rock" or "stony," a plain descriptive adjective for anything rocky in texture. Medieval French turned that into "petreux," and English took the adjective in the Middle Ages. The temporal bone of the skull has a dense, hard section that anatomists began calling the petrous part because it is as hard as stone, unlike the thinner bone around it. That is why the word, which once described ordinary rocky ground, now names a bone that shelters the delicate structures of hearing.