polystyrene

noun

poly·​sty·​rene ˌpä-lē-ˈstī-ˌrēn 

: a polymer of styrene

especially : a rigid transparent thermoplastic that has good physical and electrical insulating properties and is used especially in molded products, foams, and sheet materials

Examples of polystyrene in a Sentence

Recent Examples on the Web

Save some dough by filling the bottom third of the pot with inert materials such as blocks of polystyrene foam from product packaging or packing peanuts (secured in plastic bags). —Luke Miller, Better Homes & Gardens, 17 June 2025

Twelve states have banned polystyrene foam, which may be the reason for the switch to paper cups. —Ashley J. Dimella, FOXNews.com, 16 June 2025

Take Senate Bill 1531, legislation that would ban disposable food containers made of polystyrene foam beginning in 2030. —Patrick Gleason, Forbes.com, 9 May 2025

Thankfully, legislators in the Illinois legislature are working hard to phase out polystyrene foam, one of the worst kinds of single-use plastic. —Chicago Tribune, 18 May 2025

Word History

First Known Use

1927, in the meaning defined above

Rhymes for polystyrene

• acetylene
• adenosine
• amphetamine
• anthropocene
• antipyrine
• apomorphine
• apoprotein
• aquamarine
• arsphenamine
• azobenzene
• buprenorphine
• chlorobenzene

Kids Definition

polystyrene

noun

poly·​sty·​rene ˌpäl-i-ˈstī(ə)r-ˌēn 

: a stiff transparent plastic used chiefly in molded products, foams, and sheet materials

Medical Definition

polystyrene

noun

poly·​sty·​rene ˌpäl-i-ˈstī(ə)r-ˌēn 

: a polymer of styrene

especially : a rigid transparent thermoplastic that has good physical and electrical insulating properties and is used especially in molded products, foams, and sheet materials