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 Google is laying the groundwork for a fiber-optic network that for the first time will connect through historical enemies Saudi Arabia and Israel while opening a new corridor for global internet traffic, according to people familiar with the plans. Drew Fitzgerald, WSJ, "Google Plans Fiber-Optic Network to Connect Via Saudi Arabia and Israel for First Time," 23 Nov. 2020 Carbon fiber is a lightweight, ultrastrong material that is frequently used to form the bodies of aircraft and high-performance cars. Daniel Oberhaus, Wired, "The Batteries of the Future Are Weightless and Invisible," 6 Nov. 2020 To make up for declines in in-flight Wi-Fi, Viasat has trying to grow its residential Internet subscriber base for households outside the reach of cable or fiber-optic networks. Mike Freeman, San Diego Union-Tribune, "Viasat shuffles leadership as it moves closer to launch of new Internet satellites," 5 Nov. 2020 Foods with natural sugars tend to be nutrient-dense and also fiber-rich, providing the body with a variety of health benefits. Stefani Sassos, Ms, Rdn, Cso, Good Housekeeping, "Everything You Need to Know About the Different Types of Sugar," 29 Oct. 2020 Collected in tubes that run 40 feet from the top of the telescope to the bottom are 5,000 fiber optic cables. Shannon Stirone, Longreads, "An Atlas of the Cosmos," 29 Oct. 2020 Local provider FairPoint, which Consolidated later acquired, began expanding fiber-optic lines into Verizon territory after Verizon declined to participate in the subsidy program. Drew Fitzgerald, WSJ, "Broadband Internet Promises Are Left Unfulfilled in Many Rural Areas," 22 Oct. 2020 But its exceedingly fast speeds – 1 gigabit per second and up, rivaling fiber-optic broadband – cover exceedingly short ranges. Rob Pegoraro, USA TODAY, "On Apple iPhone 12, it's a battle of the 5G bands among AT&T, Verizon, T-Mobile," 14 Oct. 2020 By the late 1990s, investments in fiber-optic lines to carry voice, data and video were growing at a faster rate. Tom Daykin, Milwaukee Journal Sentinel, "From telegraph lines to fiber optics cables, Milwaukee's historic Wells Building legacy spans parts of two centuries," 12 Oct. 2020

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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Time Traveler for fiber

Time Traveler

The first known use of fiber was in 1607

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Statistics for fiber

Last Updated

30 Nov 2020

Cite this Entry

“Fiber.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2020.

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More Definitions for fiber


How to pronounce fiber (audio)

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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