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Synonyms

Styrofoam

American  
[stahy-ruh-fohm] / ˈstaɪ rəˌfoʊm /
Trademark.
  1. a brand of expanded plastic made from polystyrene.


Styrofoam British  
/ ˈstaɪrəˌfəʊm /

noun

  1. (sometimes not capital) a light, expanded polystyrene plastic

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Styrofoam

C20: from polystyrene + foam

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The cause of the blaze remains unclear but officials said on Friday that Styrofoam placed on the outside of the windows facilitated its rapid spread.

From BBC • Nov. 28, 2025

She then reached for a Styrofoam mannequin’s head that was on a shelf in the closet.

From Slate • Nov. 15, 2025

On blustery afternoons, my street’s geography sends every scrap of airborne litter to my curb: candy wrappers, Styrofoam peanuts and Trader Joe’s receipts that reveal too much about the neighbors’ taquitos intake.

From The Wall Street Journal • Oct. 8, 2025

Local stores will sell either Styrofoam or compostable coolers.

From Los Angeles Times • Jun. 10, 2025

The plastic forks scratched against the Styrofoam plates, the fold-up chairs squeaked and honked as people scooched up to the tables.

From "The Boy in the Black Suit" by Jason Reynolds

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