al·​lene | \ ˈaˌlēn \
plural -s

Definition of allene

1 : a gaseous hydrocarbon CH2=C=CH2

called also propadiene, sym-allylene

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

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First Known Use of allene

1875, in the meaning defined at sense 1

History and Etymology for allene

International Scientific Vocabulary, contraction of allylene

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The first known use of allene was in 1875

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Cite this Entry

“Allene.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2020.

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