fo·​lio | \ ˈfō-lē-ˌō How to pronounce folio (audio) \
plural folios

Definition of folio

 (Entry 1 of 2)

1a : a leaf especially of a manuscript or book
b : a leaf number
c : a page number
d : an identifying reference in accounting used in posting
2a : a sheet of paper folded once
b : a case or folder for loose papers
3a : the size of a piece of paper cut two from a sheet also : paper or a page of this size
b : a book printed on folio pages
c : a book of the largest size
4 : a certain number of words taken as a unit or division in a document for purposes of measurement or reference


folioed; folioing; folios

Definition of folio (Entry 2 of 2)

transitive verb

: to put a serial number on each leaf or page of

Examples of folio in a Sentence

Recent Examples on the Web: Noun

More bookshelves wrap around the eastern end of the room, holding nearly the entire collection of the society’s books, everything but the large folios. John Kelly, Washington Post, "Local history buffs rejoice: The D.C. historical society’s research collection is back," 28 Aug. 2019 The spectacular folio on the left shows Christ in majesty, enthroned in an abstract eternity of glistening, polished gold. Los Angeles Times, "Review: Unicorns are just one of the wild rides in the Getty’s marvelous ‘Book of Beasts’," 23 July 2019 Early Boomers took out mortgages instead, with housing debt ac- counting for an average of 43 percent of their household debt port- folios in their mid-twenties, compared to a housing share of only 20 percent for Millennials. The Economist, "Smashed like avocados: how young people are treated by their elders," 10 July 2019 Cramming some 600 drawings into a single leather volume containing just 234 folios was clearly challenging. Claudia Kalb, National Geographic, "Explore Leonardo da Vinci works from Queen Elizabeth II's private collection," 14 May 2019 This Gallic prodigy hands down 300 folios in which that symbol occurs on not a solitary occasion. James Geary, WSJ, "Five Best: James Geary on Works of Inspired Wit," 16 Nov. 2018 Accessories are also seeing a price bump: the new Apple Pencil 2 costs $129 — up from $99 — and the new Smart Keyboard starts at $179, the price of the most expensive version of the folio’s previous model. Natt Garun, The Verge, "Apple’s price hike strategy is paying off," 1 Nov. 2018 Apple has also improved the Apple Pencil and the smart keyboard folio. Samuel Axon, Ars Technica, "2018 iPad Pro hands-on: Improving on the world’s best tablet," 30 Oct. 2018 The folio back allows the Pixel Slate to recline to various angles (but not lie flat), or cover the tablet for safe storage in transit. Melissa Riofrio, PCWorld, "Google Pixel Slate: The top features, specs, and highlights," 9 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'folio.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of folio


15th century, in the meaning defined at sense 1a


1858, in the meaning defined above

History and Etymology for folio


Middle English, from Latin, ablative of folium

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Statistics for folio

Last Updated

9 Sep 2019

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Time Traveler for folio

The first known use of folio was in the 15th century

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More Definitions for folio


fo·​lio | \ ˈfō-lē-ˌō How to pronounce folio (audio) \

Legal Definition of folio

: a certain number of words taken as a unit or division in a document for purposes of measurement or reference

Note: A folio by statutory provision generally consists of 100 words.

More from Merriam-Webster on folio

Rhyming Dictionary: Words that rhyme with folio

Spanish Central: Translation of folio

Nglish: Translation of folio for Spanish Speakers

Comments on folio

What made you want to look up folio? Please tell us where you read or heard it (including the quote, if possible).


miscellaneous remnants or debris

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