footnote

Etymology

From foot + note.

noun

1. A short piece of text, often numbered, placed at the bottom of a printed page, that adds a comment, citation, reference etc, to a designated part of the main text.
   consult the footnotes for more details
   Above all, the 48-page timetables of the new service, which have been distributed free at every station in the scheme, are a model to the rest of B.R. For the first time on British Railways, so far as we are aware, a substantial timetable has been produced, not only without a single footnote but also devoid of all wearisome asterisks, stars, letter suffixes and other hieroglyphics. 1960 December, “The Glasgow Suburban Electrification is opened”, in Trains Illustrated, page 714
2. (by extension) An event of lesser importance than some larger event to which it is related.
   a mere footnote in history
   If we are another footnote to Plato, Plato was himself already a footnote to still earlier footnotes, in an endless chain of footnotes to footnotes 2012, Martin McQuillan, Political Archive of Paul de Man, page 72
   In that context Scotland's fate is a modest element, a symptom of wider fragmentation of the current global order, a footnote to the fall of empire and the Berlin Wall, important to us and punchdrunk neighbours like France and Italy, a mere curiosity to emerging titans like Brazil. 8 September 2014, Michael White, “Roll up, roll up! The Amazing Salmond will show a Scotland you won't believe”, in The Guardian
3. A qualification to the import of something.

verb

1. To add footnotes to a text.