noun al·lene \ˈaˌlēn\

Definition of allene



  1. 1 :  a gaseous hydrocarbon CH2=C=CH2 —called also propadiene, sym-allylene

  2. 2 :  a diolefin with its two double bonds in adjacent positions

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Origin and Etymology of allene

International Scientific Vocabulary, contraction of allylene

First Known Use: 1875

Seen and Heard

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to cast off or become cast off

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