leaf vs leaflet

leaf and leaflet both are nouns.

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

As nouns, leaflet is a hyponym of leaf; that is, leaflet is a word with a more specific, narrower meaning than leaf:

leaf (noun)	leaflet (noun)
hinged or detachable flat section (as of a table or door)	a thin triangular flap of a heart valve
a sheet of any written or printed material (especially in a manuscript or book)	a small book usually having a paper cover
the main organ of photosynthesis and transpiration in higher plants	part of a compound leaf

leaf (verb)	leaflet (verb)
produce leaves, of plants
turn over pages
look through a book or other written material