einsteinium

noun

ein·​stei·​ni·​um īn-ˈstī-nē-əm How to pronounce einsteinium (audio)
: a radioactive element produced artificially see Chemical Elements Table

Examples of einsteinium in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
By the end of the latest production campaign, the process recovered 95 percent of the einsteinium during each column run, according to ORNL. — Georgina Jedikovska, Interesting Engineering, 24 Sep. 2026

Word History

Etymology

New Latin, from Albert Einstein

First Known Use

1955, in the meaning defined above

Time Traveler
The first known use of einsteinium was in 1955

Browse Nearby Words

Einsteinian
einsteinium
Einstein law of photochemical equivalence
See all Nearby Words

Cite this Entry

“Einsteinium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/einsteinium. Accessed 9 Oct. 2026.

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Kids Definition

einsteinium

noun
ein·​stei·​ni·​um īn-ˈstī-nē-əm How to pronounce einsteinium (audio)
: a radioactive element produced artificially see element

Medical Definition

einsteinium

noun
ein·​stei·​ni·​um īn-ˈstī-nē-əm How to pronounce einsteinium (audio)
: a radioactive element produced artificially
—symbol Es see Chemical Elements Table

More from Merriam-Webster on einsteinium

Britannica.com: Encyclopedia article about einsteinium

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