fi·​ber·​glass | \ ˈfī-bər-ˌglas How to pronounce fiberglass (audio) \

Definition of fiberglass

 (Entry 1 of 2)

1 : glass in fibrous form used in making various products (such as glass wool for insulation)
2 : a composite structural material of plastic and fiberglass


fiberglassed; fiberglassing; fiberglasses

Definition of fiberglass (Entry 2 of 2)

transitive verb

: to protect or repair by applying fiberglass

Examples of fiberglass in a Sentence

Recent Examples on the Web: Noun The mural is made up of many materials, including painted metal, fiberglass, wood, blown glass and fabric — and even a bunch of watches. Washington Post, "A huge mural celebrating American workers has been two decades in the making," 6 Nov. 2019 Fire shelters are made out of aluminum foil, silica and fiberglass, and resemble a blanket. Helen Murphy,, "Hero Firefighter Protects Evacuees from Calif. Wildfire as Governor Declares Statewide Emergency," 27 Oct. 2019 He and a friend used a chisel to remove the roof, laid a little fiberglass down and installed a plastic windshield from a speed boat. Kevin Wallevand, Twin Cities, "A Minnesota bachelor farmer dies, and now his 250 cars are for sale," 8 Aug. 2019 Ardent Construction superintendent Calvin Neill says all the outside brick is being reformed, and a damaged exterior cornice will be reconstructed using fiberglass. USA TODAY, "Glowing rock fight, Statehouse stash, hometown hero: News from around our 50 states," 15 July 2019 Another plus was that South Carolina is replete with kaolin, a type of clay used in making fiberglass. Don Lee,, "Casualty of trade war: Chinese investments in U.S. grind to a halt, blocking new jobs," 1 July 2019 My poor fiberglass canoe was leaking good by the end of the trip. John Schandelmeier, Anchorage Daily News, "Denali Highway is in great shape, and caribou are there for the taking," 8 Sep. 2019 The first fiberglass mammoth was driven to the tar pits in 1967 on a trailer pulled by sculptor Howard Ball’s 1958 Volkswagen. Dorany Pinedastaff Writer, Los Angeles Times, "Mammoth memories: L.A. loves the La Brea Tar Pits’ potentially displaced creatures," 27 Aug. 2019 This makes minesweepers, wooden or fiberglass-hulled ships specifically designed to hunt down and dispose of minesweepers, vital in a conflict. Kyle Mizokami, Popular Mechanics, "The U.S. Navy’s Minesweeper Fleet Is in Bad Shape," 6 Aug. 2019

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


1937, in the meaning defined at sense 1


1967, in the meaning defined above

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Statistics for fiberglass

Last Updated

15 Nov 2019

Time Traveler for fiberglass

The first known use of fiberglass was in 1937

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More Definitions for fiberglass


How to pronounce fiberglass (audio)

English Language Learners Definition of fiberglass

: a light and strong material that is made from thin threads of glass and that is used in making various products


fi·​ber·​glass | \ ˈfī-bər-ˌglas How to pronounce fiberglass (audio) \

Kids Definition of fiberglass

: glass in the form of fibers used in various products (as filters and insulation)

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More from Merriam-Webster on fiberglass

Rhyming Dictionary: Words that rhyme with fiberglass

Spanish Central: Translation of fiberglass

Nglish: Translation of fiberglass for Spanish Speakers Encyclopedia article about fiberglass

Comments on fiberglass

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to speed up the process or progress of

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