folio in WordNet English dictionary

1. a book (or manuscript) consisting of large sheets of paper folded in the middle to make two leaves or four pages
   "the first folio of Shakespeare's plays"
   folio 
   
2. a sheet of any written or printed material (especially in a manuscript or book)
   leaf  folio 
   
3. the system of numbering pages
   pagination  folio  page number  paging