freeway vs thruway

freeway and thruway both are nouns.

Word	Noun	Adjective	Verb	Adverb
freeway	Yes	No	No	No
thruway	Yes	No	No	No

As nouns, freeway and thruway are synonyms defined as:

Other synonyms of freeway include expressway, motorway, pike, state highway, superhighway, throughway.

freeway (noun)	thruway (noun)
a broad highway designed for high-speed traffic	a broad highway designed for high-speed traffic