# polystyrene

/ˌpɑˌɫiˈstaɪˌɹin/ (US) · /pˌɒlɪstˈaɪɹiːn/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/polystyrene
Updated: 2026-05-25

## Definition

a hard, white plastic that is very light and used to make things like cups, plates, and packaging. It is also used to make foam for insulation.

For teachers: a synthetic polymer of styrene, used in the production of rigid and flexible foams, as well as disposable plastic goods. Often used in its expanded form for thermal insulation and packaging.

## Examples

- The shop uses polystyrene to keep the food warm.
- The construction company switched from wood to polystyrene for the walls to improve the building's energy efficiency.
- While polystyrene is prized for its low weight and insulating properties, its environmental impact has led many manufacturers to seek biodegradable alternatives for single-use packaging.

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