Longman Dictionary English From Longman Dictionary of Contemporary EnglishRelated topics: Plasticsthermoplasticther‧mo‧plas‧tic /ˌθɜːməʊˈplæstɪk◂ $ ˌθɜːrmə-/ noun [countable, uncountable] technicalHCP a plastic that is soft and bendable when heated but hard when cold ldoceonline.com