Dictionary.com
Thesaurus.com
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

Compare meaning

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

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.

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

He discovered the mystery blobs one day last month, initially thinking it looked like Styrofoam.

From BBC • Oct. 12, 2024

These practices included recycling, reducing food waste, not using Styrofoam, etc.

From Los Angeles Times • Sep. 15, 2024

Moses filled a Styrofoam cup of coffee for X-Ray.

From "Small Steps" by Louis Sachar

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "Styrofoam" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com