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 After taking the helm at the automaker, Musk began micromanaging everything from the fiberglass in body panels to the design of door latches. Anne Sraders, Fortune, 30 Apr. 2022 The stand has a sleek design made from thin but sturdy fiberglass, pieced together in a smart-looking Z-shape. Thomas Hindle, The Hollywood Reporter, 6 Apr. 2022 Working with industrial materials such as plastic, fiberglass, rubber, and polyester resin, Hesse explored new three-dimensional forms that married logic and chaos, sensuality and structure, order, and chance. Steven Litt, cleveland, 3 Apr. 2022 The Carex website says the rail is suitable for fiberglass tubs, because the wide plates help distribute weight evenly. Washington Post, 18 Apr. 2022 An imaginary version of this scene is burned into our collective minds and publicity campaigns like the 12-foot tall fiberglass statues in the Serpentine Lake in London’s Hyde Park in 2013 have further fueled this misconception. Emma Fraser, Town & Country, 10 Apr. 2022 And for the lungs, that means that microplastics have likely become airborne, with fibers entering the lungs in much the way same way that asbestos or fiberglass particles do. Caroline Delbert, Popular Mechanics, 7 Apr. 2022 Each of the towers are topped with a fiberglass mast and series of overhead, or catenary, wires and conductors that help divert lightning strikes away from the rocket, Parsons explained. Ashley Strickland, CNN, 3 Apr. 2022 The fiberglass design is stylish and relatively impervious to scratches and dents. Michael Verdon, Robb Report, 2 Apr. 2022 See More

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.

First Known Use of fiberglass


1937, in the meaning defined at sense 1


1967, in the meaning defined above

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The first known use of fiberglass was in 1937

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Dictionary Entries Near fiberglass



fiber grease

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Statistics for fiberglass

Last Updated

15 May 2022

Cite this Entry

“Fiberglass.” Dictionary, Merriam-Webster, Accessed 16 May. 2022.

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More Definitions for fiberglass


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)

More from Merriam-Webster on fiberglass

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


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