Styrofoam™
noun /ˈstaɪrəfəʊm/
  /ˈstaɪrəfəʊm/
(especially North American English) (also polystyrene British and North American English)
 [uncountable]- a very light soft plastic that is usually white, used especially for making containers that prevent heat loss- Styrofoam cups
 Oxford Collocations DictionaryStyrofoam™ is used before these nouns:- cup
 Word Origin1950s: from polystyrene + foam.