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 Here are a few of our top picks: Get It Together Folio ($15.39, originally $45; The perfect companion to your new planner, this folio features enough room for a legal pad and the Large 17-Month Academic Planner. Noelle Ike, CNN Underscored, "The most stylish planners we've ever seen are 30% off right now," 30 Dec. 2019 In our hands, the 2.2-pound X1 Fold felt a little chunkier than your standard writing folio or notebook, but we like where the idea is headed. Washington Post, "The future according to CES 2020: Fake meat, fake people, fake privacy," 7 Jan. 2020 Now today’s moguls have a chance to own this first folio of finance. The Economist, "A revolutionary treatise goes on the block," 6 June 2019 This text, donated to the Free Library of Philadelphia in 1944, represents the first published collection of Shakespeare’s plays and is one of around 230 folios known to survive today. Meilan Solly, Smithsonian, "Is This John Milton’s Annotated Copy of Shakespeare’s First Folio?," 17 Sep. 2019 Notably, Apple offers a leather folio for $129 for the iPhone 11 Pro, which wakes your phone up when opened and puts it to sleep when closed. Brittany Vincent, CNN Underscored, "From protection to power, here are iPhone 11 accessories you can order right now," 13 Sep. 2019 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

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

Time Traveler

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

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Statistics for folio

Last Updated

25 Feb 2020

Cite this Entry

“Folio.” Dictionary, Merriam-Webster, Accessed 26 Feb. 2020.

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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

Thesaurus: All synonyms and antonyms for folio

Rhyming Dictionary: Words that rhyme with folio

Spanish Central: Translation of folio

Nglish: Translation of folio for Spanish Speakers

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