traffic circle vs junction

traffic circle and junction both are nouns.

Word	Noun	Adjective	Verb	Adverb
traffic circle	Yes	No	No	No
junction	Yes	No	No	No

As nouns, junction is a hypernym of traffic circle; that is, junction is a word with a broader meaning than traffic circle:

traffic circle: a road junction at which traffic streams circularly around a central island
junction: the place where two or more things come together

traffic circle (noun)	junction (noun)
a road junction at which traffic streams circularly around a central island	an act of joining or adjoining things
	the place where two or more things come together
	something that joins or connects
	the shape or manner in which things come together and a connection is made
	the state of being joined together