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

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 Then in 1902, the United States Geological Survey published a large folio on metropolitan New York that detailed its rocky underpinnings, including the ridge. William J. Broad, New York Times, "How the Ice Age Shaped New York," 5 June 2018 Photo: Royal Collection Trust/Her Majesty Queen Elizabeth II The manuscript is made up of 239 folios. J.s. Marcus, WSJ, "Souvenirs of a Prince’s Passage to India," 18 May 2018 Two women from Montreal donned futuristic clothes on Sunday aiming to make the folio. David Garrick,, "Costume makers converge on San Diego for convention of creativity," 14 May 2018 The story is based on the 2004 theft of Audubon folios and rare books from the Transylvania University Special Collections Library in Lexington, Ky., by four students. Pam Grady, San Francisco Chronicle, "‘American Animals’: Playing at cops and robbers," 30 May 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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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.

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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

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