fi·​ber | \ ˈfī-bər How to pronounce fiber (audio) \

Definition of fiber

1 : a thread or a structure or object resembling a thread: such as
a(1) : a slender root (as of a grass)
(2) : an elongated tapering thick-walled plant cell void at maturity that imparts elasticity, flexibility, and tensile strength
b(1) : a strand of nerve tissue : axon, dendrite
(2) : one of the filaments composing most of the intercellular matrix of connective tissue
(3) : one of the elongated contractile cells of muscle tissue
c : a slender and greatly elongated natural or synthetic filament (as of wool, cotton, asbestos, gold, glass, or rayon) typically capable of being spun into yarn
d : mostly indigestible material in food (such as legumes, whole grains, and vegetables) that stimulates the intestine to peristalsis and promotes elimination of waste from the large intestine : bulk, roughage dietary fiber trying to get more fiber in her diet
2 : material made of fibers especially : vulcanized fiber
3a : an element that gives texture or substance
b : basic toughness : strength, fortitude
c : essential structure or character the very fiber of a person's being

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Other Words from fiber

fibered \ ˈfī-​bərd How to pronounce fibered (audio) \ adjective

Examples of fiber in a Sentence

It's important to get enough fiber in your diet. What foods do you recommend as good sources of fiber? foods that are high in fiber The fabric is made from a mix of synthetic fibers. The natural fibers allow the fabric to breathe. The paper is made from both cotton and wood fiber. Nylon is a very strong man-made fiber. The police examined hair and bits of fiber found in the victim's car.
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Recent Examples on the Web

As such, the fibers have color all the way through. Hadley Keller, House Beautiful, "Why You Should Be Using Outdoor Fabric for Basically Everything," 18 Apr. 2019 Google at the time credited the bulk of that sum to deploying its fiber network, though the company was already reconsidering the project by late 2016. Dan Gallagher, WSJ, "Google Watching Its Cable Bills," 9 Feb. 2019 Some people like the addition of oats or other fiber-rich grains in their smoothies. Samantha Cassetty, NBC News, "How to build a better smoothie, according to a nutritionist," 26 May 2018 With the requisite countdown and the push of a button, Valparaiso Mayor Jon Costas lit the city’s new dark fiber network at a recent City Council meeting. Amy Lavalley, Post-Tribune, "Valparaiso embraces dark fiber network as it eyes business growth," 18 May 2018 Each home is hardwired to a fiber network infrastructure capable of downloading a movie in a few seconds. Jack Flemming,, "As millennials buy more homes, developers strategize to bring them in," 11 May 2018 File photo of Mark Strama, head of Google Fiber Texas, speaking at a 2015 press conference announcing plans to expanded its fiber network to San Antonio. Rye Druzin, San Antonio Express-News, "Google Fiber expanding San Antonio service on Far West Side," 29 Mar. 2018 In the eastern part of the state, Tunbridge's Vermont Sheep & Wool Festival showcases more than 70 vendors selling fleece, yarn, and hand-spun fabrics; there's also a cashmere exhibit and fiber arts classes. Cassie Shortsleeve, Condé Nast Traveler, "See Vermont Fall Foliage in These 12 Beautiful Places," 2 Oct. 2018 Wisconsin Museum of Quilts & Fiber Arts: Lectures and classes for all adults, beginner to advanced, on a variety of fiber arts topics. Elaine Rewolinski, Milwaukee Journal Sentinel, "A listing of home and garden events for the Milwaukee area (Summer 2018 edition)," 4 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fiber.' 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 fiber

1607, in the meaning defined at sense 1

History and Etymology for fiber

Middle French fibre, from Latin fibra

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Dictionary Entries near fiber

fiat money





fiber box

fiber can

Statistics for fiber

Last Updated

13 May 2019

Look-up Popularity

Time Traveler for fiber

The first known use of fiber was in 1607

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More Definitions for fiber



English Language Learners Definition of fiber

: plant material that cannot be digested but that helps you to digest other food
: a thin thread of natural or artificial material that can be used to make cloth, paper, etc.
: material (such as cloth) that is made from thin threads : something made of fibers


fi·​ber | \ ˈfī-bər How to pronounce fiber (audio) \

Kids Definition of fiber

1 : a thread or a structure or object resembling a thread
2 : plant material that cannot be digested


variants: or chiefly British fibre \ ˈfī-​bər How to pronounce fibre (audio) \

Medical Definition of fiber

1 : a thread or a threadlike structure or object: as
a : a strand of nerve tissue : axon, dendrite
b : one of the filaments composing most of the intercellular matrix of connective tissue
c : one of the elongated contractile cells of muscle tissue
2 : mostly indigestible material in food that stimulates the intestine to peristalsis

called also bulk, dietary fiber, roughage

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More from Merriam-Webster on fiber

Rhyming Dictionary: Words that rhyme with fiber

Thesaurus: All synonyms and antonyms for fiber

Spanish Central: Translation of fiber

Nglish: Translation of fiber for Spanish Speakers

Britannica English: Translation of fiber for Arabic Speakers Encyclopedia article about fiber

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using a distributed computer network

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