fi·​ber·​glass | \ ˈfī-bər-ˌglas \

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

Floyd, who invented the heated bench, uses hollowed fiberglass and propane- or natural-gas-powered blowers running at 170,000 Btus to keep the player posteriors toasty warm. Tim Newcomb, Popular Mechanics, "How NFL Fields, and Players, Stay Warm for Winter Games," 16 Jan. 2019 The arm is connected to a tube on the ground that feeds a mix of fiberglass and resin into the robot to create the wet filament. Liz Stinson, Curbed, "Watch a swarm of robots build a fiber structure," 12 Oct. 2018 Portable units sit aboveground and are made from fiberglass, polyethylene, or acrylic. Timothy Dahl, Popular Mechanics, "How to Buy a Hot Tub That Your Whole Family Will Enjoy," 30 Jan. 2019 One corner of the exhibition offers yet more context: The Design Fictions section showcases a 1947 flying car, a midcentury levitating concept car, a 1960s car with a desk inside, and a 1963 one-piece fiberglass car. Diana Budds, Curbed, "The future of urban mobility will be shaped by these six issues," 18 Dec. 2018 Typically, filters are made of paper, fiber (often fiberglass), or mesh, and require regular replacement to maintain efficiency. Rachel Rothman, Good Housekeeping, "Do Air Purifiers Actually Work?," 17 Dec. 2018 For her entrance look, Trinity paired the ensemble with a choker and fiberglass earrings, making a bracelet from leftover zip tie material just before walking into the workroom herself. Steff Yotka, Vogue, "From Runway to Red Carpet to RuPaul’s Drag Race: How Trinity The Tuck Paid Homage to Sarah Paulson’s Prada Look," 13 Dec. 2018 On the rose-and-white model, the palm rest area and space around the keyboard are covered with a very nice fiberglass-like weave that gives it a bit of texture and makes for a little bit softer edge. Scott Gilbertson, Ars Technica, "The 2018 XPS 13 Developer’s Edition—Have it your way on a “just works” Linux laptop," 12 Dec. 2018 Each would have a seismometer to measure ground movement, 10 batteries in a fiberglass enclosure with solar panels, and antennae for GPS and data transfer, according to a report from the Forest Service. Kari Bray, The Seattle Times, "‘Very high threat’ Snohomish County volcano may get new monitoring stations," 19 Aug. 2018

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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Last Updated

22 Feb 2019

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Time Traveler for fiberglass

The first known use of fiberglass was in 1937

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More Definitions for fiberglass



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 \

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

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a servile follower or underling

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