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cyclopentadiene

noun
cy·​clo·​pentadiene
plural -s

Definition of cyclopentadiene

: a colorless liquid unsaturated cyclic hydrocarbon C5H6 that is obtained by distillation of coal tar, that polymerizes to its stable dimer on standing, and is used in making plastics and insecticides

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History and Etymology for cyclopentadiene

International Scientific Vocabulary cycl- + pentadiene (from pent- + di- + -ene)

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