Styrofoam

trademark

Sty·​ro·​foam ˈstī-rə-ˌfōm How to pronounce Styrofoam (audio)
—used for an expanded rigid polystyrene plastic

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“Styrofoam.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Styrofoam. Accessed 2 Aug. 2026.

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Styrofoam

trademark
Sty·​ro·​foam ˈstī-rə-ˌfōm How to pronounce Styrofoam (audio)
—used for an expanded stiff plastic
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