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

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

Made from sleek ceramic epoxy over fiberglass, the stacked dishes are piled tilting this way and that.

From Los Angeles Times • Nov. 25, 2025

In a locker behind the wheel pedestal he found coils of nylon rope and steel bottles of gas and a toolbox made of fiberglass.

From "The Road" by Cormac McCarthy