'Brownstone' definitions:

Definition of 'brownstone'

From: WordNet
noun
A reddish brown sandstone; used in buildings
noun
A row house built of brownstone; reddish brown in color

Definition of 'Brownstone'

From: GCIDE
  • Brownstone \Brown"stone`\, n.
  • 1. A dark variety of sandstone, much used for building purposes. [1913 Webster]
  • 2. a building, especially a dwelling, faced with brownstone[1]. [PJC]