I. ˈfōlēˌō, -ōlˌyō noun
( -s )
Etymology: Middle English, from Latin, abl. of folium leaf of a tree, leaf of paper — more at blade
1.
a. : a leaf especially of a manuscript or book
b. : a leaf number
a school workbook in which writing is to appear on only one side of the leaf often has folios on the right-hand pages
c. : a page number
in books the even folios are on the left-hand pages and the odd folios on the right-hand pages
d. : an identifying reference in accounting used in posting to indicate source of entry and account to which entered
2.
a. : a sheet of paper folded once
b. : a case or folder for loose papers
3.
a. : the size or form of a folio book
books in folio
b. : a folio book or publication
c. : a book of the largest size — see book tables
d. : the size of a piece of paper cut two from a sheet ; also : paper or a page of this size — abbr. fo or f ; symbol F ; see book tables
4. : a certain number of words taken as a unit or division in a document for purposes of measurement or reference (as in Great Britain and Ireland 72 or 90 and in the United States generally 100 by statutory provision)
5. also folio post : a certain size (as 17 × 22 inches) of a sheet of especially writing or ledger paper
II. adjective
1. : formed of sheets each folded once into two leaves or four pages
a folio edition
a work in five volumes folio
2.
a. : of the size of a folio book
a folio case
a huge folio atlas
b. : produced in folio
to the bibliographer … a book made up in octavo format may be the same size as one in folio format, depending on the size of the sheet used for the text — Edith Diehl
3. : of full size and not folded — used of sheets and reams of paper
III. transitive verb
( -ed/-ing/-s )
1. : to put a serial number on each leaf or each page of (a manuscript or a book) — compare foliate , page
2. law : to mark with its number each folio in (as a pleading, brief, affidavit)