polystyrene
noun
poly·sty·rene
ˌpä-lē-ˈstī-ˌrēn 
: 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
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Made from recyclable, all-weather polystyrene that is designed to last and never fade, the bench looks like real wood without the threat of rot and termites.
—
Stephanie Osmanski, Better Homes & Gardens, 16 Sep. 2025
Microplastics are tiny plastic fragments, less than five millimeters long, derived from the breakdown of larger plastics or manufactured at that size for commercial use; common polymers include polyethylene, polypropylene, polyvinyl chloride, and polystyrene.
—Melissa Cristina Márquez, Forbes.com, 16 Sep. 2025
The technique usually relies on hollow glass spheres, polystyrene beads, aluminum flakes, or synthetic granules with special optical coatings to enhance the reflection of light.
—Ashley Belanger, ArsTechnica, 22 Aug. 2025
The law also banned polystyrene food containers like cups, plates and clamshell boxes, commonly known as Styrofoam, statewide, effective Jan. 1 of this year.
—Paul Rogers, Mercury News, 19 Aug. 2025
See All Example Sentences for polystyrene
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Stephanie Osmanski, Better Homes & Gardens, 16 Sep. 2025
Microplastics are tiny plastic fragments, less than five millimeters long, derived from the breakdown of larger plastics or manufactured at that size for commercial use; common polymers include polyethylene, polypropylene, polyvinyl chloride, and polystyrene.
—Melissa Cristina Márquez, Forbes.com, 16 Sep. 2025
The technique usually relies on hollow glass spheres, polystyrene beads, aluminum flakes, or synthetic granules with special optical coatings to enhance the reflection of light.
—Ashley Belanger, ArsTechnica, 22 Aug. 2025
The law also banned polystyrene food containers like cups, plates and clamshell boxes, commonly known as Styrofoam, statewide, effective Jan. 1 of this year.
—Paul Rogers, Mercury News, 19 Aug. 2025
See All Example Sentences for polystyrene
Cite this Entry
“Polystyrene.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polystyrene. Accessed 19 Sep. 2025.
Copy CitationKids Definition
polystyrene
noun
poly·sty·rene
ˌpäl-i-ˈstī(ə)r-ˌēn
: 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
: 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
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