fiberglass

American  

[fahy-ber-glas, -glahs] / ˈfaɪ bərˌglæs, -ˌglɑs /

Or fiber glass

noun

1. a material consisting of extremely fine filaments of glass that are combined in yarn and woven into fabrics, used in masses as a thermal and acoustical insulator, or embedded in various resins to make boat hulls, fishing rods, and the like.

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verb (used with object)

1. to cover or form with fiberglass.

verb (used without object)

1. to use or work with fiberglass.

fiberglass Scientific  

/ fī′bər-glăs′ /

1. A material made up of very fine fibers of glass. Fiberglass is resistant to heat and fire and is used to make various products, such as building insulation and boat hulls. Because the fibers in fiberglass are capable of transmitting light around curves, fiberglass is an important component of fiber optics.

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Etymology

Origin of fiberglass

An Americanism dating back to 1935–40; fiber + glass

Example Sentences

See Examples For:

fiberglass

Nearby fields were littered with broken deckchairs, scraps of fiberglass insulation and pieces of wire fencing ripped apart by the fierce winds that struck the village and its surroundings.

From Barron's ● Aug. 25, 2026

So I had all these giddy, kind of rose-tinted romantic notions of what I was doing until I was knee-deep in fiberglass, going, “Why did I think this was a good idea?”

From Los Angeles Times ● Aug. 20, 2026

For decades, the company has been recognized for its mascot, a pink panther that matches the color of its signature bright pink fiberglass insulation.

From The Wall Street Journal ● Jun. 29, 2026

The 2nd Amendment Cowboy is a fiberglass giant that stands at the entrance to a trailer park near the art installation Cadillac Ranch in Amarillo, Texas.

From Los Angeles Times ● May 12, 2026

John studied the notch in his fiberglass harpoon.

From "Adrift" by Paul Griffin