polystyrene

noun

poly·​sty·​rene ˌpä-lē-ˈstī-ˌrēn How to pronounce polystyrene (audio)
: a polymer of styrene
especially : a rigid transparent thermoplastic that has good physical and electrical insulating properties and is used especially in molded products, foams, and sheet materials

Examples of polystyrene in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Twelve-micrometer polystyrene films got punched through while 130-micrometer films survived. — Jacek Krywko, ArsTechnica, 31 Aug. 2026 Niutech explained the technology can process polypropylene, polyethylene, polystyrene, acrylonitrile butadiene styrene and nylon, either separately or in mixed streams. — Bojan Stojkovski, Interesting Engineering, 30 Aug. 2026 Each cooler box is individually handcrafted in Cape Town, South Africa, from a combination of plastic, polystyrene, aluminum, leather, brass, steel, and silicone. — Alison Fox, Travel + Leisure, 27 July 2026 As new laws restrict the use of polystyrene, the industry is pushing back and trying to rehabilitate the material’s image. — Bloomberg, Mercury News, 16 July 2026 See All Example Sentences for polystyrene

Word History

First Known Use

1927, in the meaning defined above

Time Traveler
The first known use of polystyrene was in 1927

Rhymes for polystyrene

See All Rhymes for polystyrene

Browse Nearby Words

polystyle
polystyrene
polysulfide
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Cite this Entry

“Polystyrene.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polystyrene. Accessed 4 Sep. 2026.

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Kids Definition

polystyrene

noun
poly·​sty·​rene ˌpäl-i-ˈstī(ə)r-ˌēn How to pronounce polystyrene (audio)
: a stiff transparent plastic used chiefly in molded products, foams, and sheet materials

Medical Definition

polystyrene

noun
poly·​sty·​rene ˌpäl-i-ˈstī(ə)r-ˌēn How to pronounce polystyrene (audio)
: a polymer of styrene
especially : a rigid transparent thermoplastic that has good physical and electrical insulating properties and is used especially in molded products, foams, and sheet materials

More from Merriam-Webster on polystyrene

Britannica.com: Encyclopedia article about polystyrene

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