noun ·Uncommon ·Advanced level

Definitions

Noun

1. 1
   Expanded polystyrene foam, such as is used in cups and packaging. countable, uncountable

   "A while ago I read your column concerning the effects of hot tea on styrofoam cups."

2. 2
   a light resilient foam of polystyrene wordnet

Synonyms

All synonyms

acrylicaeroboardaeroboardplastic

Example

More examples

"Tom was drinking coffee out of a Styrofoam cup."

Etymology

Genericized trademark of Styrofoam, from -styr- (from polystyrene) + -o- + foam.

Related phrases

styrofoam popcorn

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.