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English definition of “polystyrene”


noun [U]     /ˌpɒl.ɪˈstaɪ.riːn/ US  /ˌpɑː.lɪˈstaɪ-/ (US usually trademark Styrofoam)
a light, usually white plastic used especially for putting around delicate objects inside containers to protect them from damage, or for putting around something to prevent it from losing heat: polystyrene cups/plates The ceiling was covered with polystyrene insulation tiles.Plastics and rubberWrapping, packing and loading
(Definition of polystyrene noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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