allene

noun

al·​lene

ˈaˌlēn

plural -s

1

: a gaseous hydrocarbon CH₂=C=CH₂

called also propadiene, sym-allylene

2

: a diolefin with its two double bonds in adjacent positions

Word History

Etymology

International Scientific Vocabulary, contraction of allylene

First Known Use

1875, in the meaning defined at sense 1

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