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

To avoid triggering magnetic mines, the hulls are constructed of wood and fiberglass.

From The Wall Street Journal • Mar. 12, 2026

After ogling old cars, lean into nostalgia in the Meadow Gold District, dotted with retro shops and “muffler men,” giant fiberglass statues of a lumberjack, a cowboy and more.

From The Wall Street Journal • Dec. 20, 2025

The Charter Communications network is made of fiber-optic cables, created from fiberglass and plastic, which deliver faster internet speeds, require less maintenance and don’t have resale value.

From The Wall Street Journal • Nov. 29, 2025

Skaters are lacing up their customized Stacy Adams boots, which are fully equipped with fiberglass wheels.

From Los Angeles Times • Apr. 16, 2025

We’d propped it up on one side with the Windsurfer’s fiberglass crossbeam so we had a clear view of the water.

From "Adrift" by Paul Griffin