ce·​ri·​um | \ ˈsir-ē-əm How to pronounce cerium (audio) \

Definition of cerium

: a malleable ductile metallic element that is the most abundant of the rare-earth group — see Chemical Elements Table

Examples of cerium in a Sentence

Recent Examples on the Web

Next door to the oven, more than 150 bags of neodymium and praseodymium and cerium sat on a warehouse floor to be shipped to customers around the world. Alexandra Stevenson, New York Times, "How Rare Earths (What?) Could Be Crucial in a U.S.-China Trade War," 11 July 2018 Marine scientists at China’s Guangxi Key Laboratory recently deduced the strength of East Asian winter monsoons over the past 150 years by measuring levels of rare earth elements, such as lanthanum and cerium, in each layer of a Poritescoral core. Elizabeth Svoboda, Scientific American, "Cores from Coral Reefs Hold Secrets of the Seas’ Past and Future," 6 June 2018 Instead of neodymium or dysprosium, the magnet uses less-expensive rare-earth metals lanthanum and cerium. Megan Geuss, Ars Technica, "Toyota’s new magnet won’t depend on some key rare-earth minerals," 28 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cerium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cerium

1804, in the meaning defined above

History and Etymology for cerium

New Latin, from Ceres, an asteroid

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Statistics for cerium

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Time Traveler for cerium

The first known use of cerium was in 1804

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More Definitions for cerium


ce·​ri·​um | \ ˈsir-ē-əm How to pronounce cerium (audio) \

Medical Definition of cerium

: a malleable ductile metallic element that is the most abundant of the rare-earth group symbol Ce — see Chemical Elements Table

More from Merriam-Webster on cerium

Britannica.com: Encyclopedia article about cerium

Comments on cerium

What made you want to look up cerium? Please tell us where you read or heard it (including the quote, if possible).


incapable of being surmounted or overcome

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