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

This week, the bloc also agreed to double tariffs on steel imports above a certain quota and impose antidumping rules on fiberglass.

From The Wall Street Journal ● Apr. 17, 2026

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

From The Wall Street Journal ● Mar. 12, 2026

For 48 years, Kaplan rode a fiberglass skateboard.

From Los Angeles Times ● Jan. 26, 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

The design of my left leg had changed, and the metal poles and clump of metal for a foot had been traded in for fiberglass.

From "Ugly" by Robert Hoge