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brownstone

American  
[broun-stohn] / ˈbraʊnˌstoʊn /

noun

  1. a reddish-brown sandstone, used extensively as a building material.

  2. Also called brownstone front.  a building, especially a row house, fronted with this stone.


adjective

  1. Archaic. belonging or pertaining to the well-to-do class.

brownstone British  
/ ˈbraʊnˌstəʊn /

noun

  1. a reddish-brown iron-rich sandstone used for building

  2. a house built of or faced with this stone

"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

Etymology

Origin of brownstone

First recorded in 1830–40; brown + stone