circular vs rotary

circular and rotary both are nouns.

Word	Noun	Adjective	Verb	Adverb
circular	Yes	Yes	No	No
rotary	Yes	Yes	No	No

As adjectives, circular and rotary are synonyms defined as:

Other synonyms of circular include orbitual.

circular (noun)	rotary (noun)
an advertisement (usually printed on a page or in a leaflet) intended for wide distribution	a road junction at which traffic streams circularly around a central island
	electrical converter consisting of a synchronous machine that converts alternating to direct current or vice versa

circular (adjective)	rotary (adjective)
having the shape or form of a circle	relating to or characterized by rotation
describing a circle; moving in a circle	describing a circle; moving in a circle