Definition of Rowley rag in US English:

Rowley rag

noun

Geology
  • A hard, dark-coloured, fine-grained basaltic rock from Rowley Hill near Birmingham, England, formerly used for paving and in building work.

Origin

Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London. From the names of RowleyRegis, a town near Birmingham, England and RowleyHill, the hill on which the town is located, and from which the stone was quarried + rag.

Pronunciation

Rowley rag

/ˌraʊli ˈraɡ/