beltway vs ring road

beltway and ring road both are nouns.

Word	Noun	Adjective	Verb	Adverb
beltway	Yes	No	No	No
ring road	Yes	No	No	No

As nouns, beltway and ring road are synonyms defined as:

beltway and ring road: a highway that encircles an urban area so that traffic does not have to pass through the center

Other synonyms of beltway include bypass, ringway.

beltway (noun)	ring road (noun)
a highway that encircles an urban area so that traffic does not have to pass through the center	a highway that encircles an urban area so that traffic does not have to pass through the center