row house vs brownstone

row house and brownstone both are nouns.

Word	Noun	Adjective	Verb	Adverb
row house	Yes	No	No	No
brownstone	Yes	No	No	No

As nouns, brownstone is a hyponym of row house; that is, brownstone is a word with a more specific, narrower meaning than row house:

row house: a house that is one of a row of identical houses situated side by side and sharing common walls
brownstone: a row house built of brownstone; reddish brown in color

Other hyponyms of row house include terraced house.

row house (noun)	brownstone (noun)
a house that is one of a row of identical houses situated side by side and sharing common walls	a row house built of brownstone; reddish brown in color
	a reddish brown sandstone; used in buildings