circular vs flyer

circular and flyer both are nouns.

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

As nouns, circular and flyer are synonyms defined as:

circular and flyer: an advertisement (usually printed on a page or in a leaflet) intended for wide distribution

Other synonyms of circular include bill, broadsheet, broadside, flier, handbill, throwaway.

circular (noun)	flyer (noun)
an advertisement (usually printed on a page or in a leaflet) intended for wide distribution	an advertisement (usually printed on a page or in a leaflet) intended for wide distribution
	someone who travels by air
	someone who operates an aircraft

circular (adjective)	flyer (adjective)
having the shape or form of a circle
describing a circle; moving in a circle