folio

 
Pronunciation: /ˈfəʊlɪəʊ/

noun (plural folios)

  • 1an individual leaf of paper or parchment, either loose as one of a series or forming part of a bound volume, which is numbered on the recto or front side only.
  • the page number in a printed book.
  • 2a sheet of paper folded once to form two leaves (four pages) of a book.
  • a size of book made up of folio sheets of paper.
  • a book or manuscript made up of folio sheets of paper; a volume of the largest standard size.

Origin:

late Middle English: from Latin, ablative of folium 'leaf', in medieval Latin used in references to mean 'on leaf so-and-so'. The original sense of in folio (from Italian in foglio) was 'in the form of a full-sized sheet or leaf folded once' (designating the largest size of book)