polystyrene

American  

[pol-ee-stahy-reen, -steer-een] / ˌpɒl iˈstaɪ rin, -ˈstɪər in /

noun

Chemistry.

1. a clear plastic or stiff foam, a polymer of styrene, used chiefly as an insulator in refrigerators and air conditioners.

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polystyrene British  

/ ˌpɒlɪˈstaɪriːn /

noun

1. a synthetic thermoplastic material obtained by polymerizing styrene; used as a white rigid foam ( expanded polystyrene ) for insulating and packing and as a glasslike material in light fittings and water tanks

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polystyrene Scientific  

/ pŏl′ē-stī′rēn /

1. A brittle synthetic polymer composed of repeated styrene units. Polystyrene is transparent and rigid because the benzene rings in each styrene unit prevent the polystyrene chains from arranging themselves into a tight crystalline structure. Polystyrene has a wide variety of uses, especially as a solid foam for insulation and packaging.

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Etymology

Origin of polystyrene

First recorded in 1925–30; poly- + styrene

Compare meaning

How does polystyrene compare to similar and commonly confused words? Explore the most common comparisons:

• polystyrene vs. Styrofoam

Example Sentences

Dell pointed to SB 54’s de facto ban on polystyrene, which went into effect on Jan. 1, 2025.

From Los Angeles Times

But critics say the boutique waste hauler is not accomplishing anything environmentally useful and is selling the public a myth: that these plastics — multilayer plastic film, plastic bags, polystyrene — can be taken care of responsibly.

From Los Angeles Times

Based on the amount of polystyrene particles in one square metre, David estimated that there were over 300,000 pieces lying across 70 square metres.

From BBC

The light polystyrene craft resembles a toy plane.

From Barron's

Airport authorities and police seized six pieces of rhinoceros horn and around 12 kilograms of unidentified meat used to conceal them inside a polystyrene icebox.

From Barron's