The Collaborative International Dictionary of English v.0.48:
Footnote \Foot"note`\, n. A note of reference or comment at the foot[4] of a page. [1913 Webster]WordNet (r) 3.0 (2006):
footnote n 1: a printed note placed below the text on a printed page [syn: footnote, footer] v 1: add explanatory notes to or supply with critical comments; "The scholar annotated the early edition of a famous novel" [syn: annotate, footnote]