Simple Definition of Styrofoam

from our Learner's Dictionary

Styrofoam

trademark

ˈstaɪrəˌfoʊm How to pronounce Styrofoam (audio)
—used for a type of light and usually white plastic

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“Styrofoam.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/Styrofoam. Accessed 21 Jun. 2026.

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