leaflet vs folder

leaflet and folder both are nouns.

Word	Noun	Adjective	Verb	Adverb
leaflet	Yes	No	No	No
folder	Yes	No	No	No

As nouns, leaflet and folder are synonyms defined as:

Other synonyms of leaflet include booklet, brochure, pamphlet.

leaflet (noun)	folder (noun)
a thin triangular flap of a heart valve	covering that is folded over to protect the contents
a small book usually having a paper cover	a small book usually having a paper cover
part of a compound leaf