thermoplastic

American  

[thur-muh-plas-tik] / ˌθɜr məˈplæs tɪk /

adjective

1. soft and pliable when heated, as some plastics, without any change of the inherent properties.

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noun

1. a plastic of this type.

thermoplastic British  

/ ˌθɜːməʊplæˈstɪsɪtɪ, ˌθɜːməʊˈplæstɪk /

adjective

1. (of a material, esp a synthetic plastic or resin) becoming soft when heated and rehardening on cooling without appreciable change of properties Compare thermosetting

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noun

1. a synthetic plastic or resin, such as polystyrene, with these properties

thermoplastic Scientific  

/ thûr′mə-plăs′tĭk /

1. Of or relating to a compound that can be repeatedly made soft and hard through heating and cooling. Polyethylene and polystyrene are thermoplastic resins.

2. Compare thermosetting

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Other Word Forms

• nonthermoplastic
  adjective
• thermoplasticity
  noun

Etymology

Origin of thermoplastic

First recorded in 1880–85; thermo- + plastic

Example Sentences

To further improve flexibility, the team incorporated a thermoplastic polyurethane elastomer matrix into the ExciPh layer.

From Science Daily • Jan. 15, 2026

The thermoplastic polyurethane rubber-shelled boots are straight out of a world like Roger Rabbit’s, where the lines between cartoons and humans are blurred.

From Los Angeles Times • Feb. 16, 2023

Another work, “Inverted Monument,” looks like an upside-down statue trapped inside a semitransparent pedestal, and is made of extruded thermoplastic polyester threads.

From New York Times • Aug. 30, 2022

In Renton, new robotic cells automate the manufacture of thermoplastic parts from carbon fiber composites.

From Seattle Times • Jul. 20, 2022

The seams adhere with tape or, if a thermoplastic membrane is used, seams are heated so they meld together to create a seal.

From Washington Post • Mar. 15, 2022