plural archaeans
: any of the microorganisms comprising the archaea
In earlier work on the mine ecosystem, these archaeans had gone undetected.—
Henry Nicholls
Henry Nicholls
archaean
adjective
archaean thermophiles
archaean species
Examples of Archaean in a Sentence
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Katherine Bourzac, Quanta Magazine, 15 Sep. 2025
Pyrodictium is an archaean that lives in scalding-hot waters off Sicily, near the island of Vulcano, and that uses the reaction between sulphur and hydrogen for energy.
—Tim Flannery, The New York Review of Books, 17 Nov. 2020
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Noun
Ancient archaean cells used the reaction between hydrogen gas and carbon to make energy for themselves, and released methane gas as a by-product.
—Katherine Bourzac, Quanta Magazine, 15 Sep. 2025
Pyrodictium is an archaean that lives in scalding-hot waters off Sicily, near the island of Vulcano, and that uses the reaction between sulphur and hydrogen for energy.
—Tim Flannery, The New York Review of Books, 17 Nov. 2020
Cite this Entry
“Archaean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Archaean. Accessed 4 Nov. 2025.
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