How Well Do You Know English Slang?
part of a French newspaper devoted to light literature and criticism (usually at the bottom of a page and separated by a rule), 1845, from French feuilleton (18c.), literally "a leaflet (added to a newspaper)," diminutive of feuille "leaf," from Latin folium (see folio).
Esp. applied in F. to the short story or serial with which newspapers filled up after the fall of Napoleon left them short of war news. This was the beginning of Dumas' and Eugène Sue's long novels. [Weekley]