# fiberglass

/ˈfaɪbɝˌɡɫæs/ (US) · CEFR B2 · Noun

Source: https://englishreference.com/word/fiberglass
Updated: 2026-05-11

## Definition

a strong, light material made from tiny threads of glass. It is often used to build things like boats, cars, and insulation for houses.

For teachers: a reinforced plastic material composed of glass fibres embedded in a resin matrix. Often used for its high strength-to-weight ratio and thermal insulation properties.

## Examples

- The boat has a strong fiberglass hull.
- Workers wore protective masks while installing fiberglass insulation in the attic to avoid breathing in the tiny glass particles.
- Modern aerospace engineering frequently utilizes fiberglass and other composite materials to reduce aircraft weight while maintaining the structural integrity required for high-altitude flight.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.