stuffer vs flyer

stuffer and flyer both are nouns.

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

As nouns, flyer is a hypernym of stuffer; that is, flyer is a word with a broader meaning than stuffer:

stuffer: an advertising circular that is enclosed with other material and (usually) sent by mail
flyer: an advertisement (usually printed on a page or in a leaflet) intended for wide distribution

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

stuffer (noun)	flyer (noun)
an advertising circular that is enclosed with other material and (usually) sent by mail	an advertisement (usually printed on a page or in a leaflet) intended for wide distribution
a craftsman who stuffs and mounts the skins of animals for display	someone who travels by air
	someone who operates an aircraft