folio

American  

[foh-lee-oh] / ˈfoʊ liˌoʊ /

noun

plural

folios

1. a sheet of paper folded once to make two leaves, or four pages, of a book or manuscript.

2. a volume having pages of the largest size, formerly made from such a sheet.

3. a leaf of a manuscript or book numbered only on the front side.

4. a case that, when closed, covers and protects both the screen and the back panel of a mobile device, as a tablet or smartphone.

5. Printing.

   1. (in a book) the number of each page.

   2. (in a newspaper) the number of each page together with the date and the name of the newspaper.

6. Bookkeeping. a page of an account book or a left-hand page and a right-hand page facing each other and having the same serial number.

7. Law. a certain number of words, in the U.S. generally 100, taken as a unit for computing the length of a document.

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adjective

1. pertaining to or having the format of a folio.

   a folio volume.

verb (used with object)

folioed, folioing

1. to number each leaf or page of.

2. Law. to mark each folio in (a pleading or the like) with the proper number.

folio British  

/ ˈfəʊlɪəʊ /

noun

1. a sheet of paper folded in half to make two leaves for a book or manuscript

2. a book or manuscript of the largest common size made up of such sheets

3. a leaf of paper or parchment numbered on the front side only

4. a page number in a book

5. law a unit of measurement of the length of legal documents, determined by the number of words, generally 72 or 90 in Britain and 100 in the US

6. a collection of related material

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adjective

1. relating to or having the format of a folio

   a folio edition

verb

1. (tr) to number the leaves of (a book) consecutively

Etymology

Origin of folio

1525–35; < Latin foliō (originally in phrase in foliō in a leaf, sheet), ablative of folium folium

Explanation

A folio is an old fashioned kind of book, typically made of large folded sheets of paper. In the 1600s, many of Shakespeare's plays were printed in the form of a folio. The word folio means "leaf or sheet of paper" in Latin. A folio is made by folding one piece of paper in half — counting each side, this gives you four pages. A larger folio is simply a collection of many folded sheets bound together. In the early days of printing, the fanciest books were folios. Another method was the quarto, with two folds in each sheet and pages that had to be cut open after they were bound.

Example Sentences

A dog-eared punk zine flutters near a vellum-bound folio.

From Los Angeles Times • Oct. 7, 2025

They’ll be kicking themselves because somewhere in the fine print or in their hotel folio, the mandatory extras were disclosed.

From Seattle Times • May 27, 2024

The folio edition was compiled by actors John Heminge and Henry Condell as a tribute and memorial to the writer.

From BBC • Apr. 24, 2023

Another chapter patiently explains, with illustrations, the process of printing a large folio.

From Washington Post • Apr. 21, 2023

“Commandant says you’re to take that folio to Spiro Teluman first thing, before attending to your other duties.”

From "An Ember in the Ashes" by Sabaa Tahir

Related Words

• album
• booklet
• brochure
• copy
• dictionary
• edition
• essay
• fiction
• magazine
• manual
• novel
• pamphlet
• paperback
• publication
• text
• textbook
• tome
• volume
• work
• writing