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

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

A spider can flick off irritating hairs from the backside of its abdomen, which feel like fiberglass or minute cactus spines.

From Los Angeles Times • Oct. 25, 2025

The fiberglass screeched each time John sawed it.

From "Adrift" by Paul Griffin