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

Word History


alkene + -one

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of alkenone was in 1945

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Cite this Entry

“Alkenone.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2023.

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