al·​ke·​none | \ ˈal-kə-ˌnōn How to pronounce alkenone (audio) \
plural alkenones

Definition of alkenone

: any of various long-chain unsaturated ketones that are produced by phytoplanktonic algae (such as the coccolithophores)

Note: Analysis of the chemical structure of alkenones present in marine sediment is used as a method to determine past sea temperatures.

To further the current climate debate, the chapter “Deep Sea Mud” explains how compounds such as alkenones, left by the marine alga Emiliania huxleyi, among other species, provide a temperature proxy.— Karen Bushaw-Newton, Bioscience, 1 Sept. 2009

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First Known Use of alkenone

1945, in the meaning defined above

History and Etymology for alkenone

alkene + -one

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The first known use of alkenone was in 1945

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Cite this Entry

“Alkenone.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

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