[ sahy-kluh-pen-tuh-dahy-een, sik-luh- ]
/ ˌsaɪ kləˌpɛn təˈdaɪ in, ˌsɪk lə- /


a colorless liquid, C5H6, derived by the distillation of coal tar: used chiefly in the manufacture of insecticides and resins.


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Origin of cyclopentadiene Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for cyclopentadiene

/ (ˌsaɪkləʊˌpɛntəˈdaɪiːn) /


a colourless liquid unsaturated cyclic hydrocarbon obtained in the cracking of petroleum hydrocarbons and the distillation of coal tar: used in the manufacture of plastics and insecticides. Formula: C 5 H 6
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012