promethium

noun
pro·​me·​thi·​um | \ prə-ˈmē-thē-əm How to pronounce promethium (audio) \

Definition of promethium

: a radioactive metallic element of the rare-earth group obtained as a fission product of uranium or from neutron-irradiated neodymium — see Chemical Elements Table

Examples of promethium in a Sentence

Recent Examples on the Web One promethium isotope, with eighty-eight neutrons, has a half-life of a few days; the other, with eighty-six neutrons, has a half-life of a few years. Neima Jahromi, The New Yorker, "The Histories Hidden in the Periodic Table," 27 Dec. 2019

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

First Known Use of promethium

1948, in the meaning defined above

History and Etymology for promethium

New Latin, from Latin Prometheus

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Time Traveler for promethium

Time Traveler

The first known use of promethium was in 1948

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Cite this Entry

“Promethium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/promethium. Accessed 20 Oct. 2020.

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More Definitions for promethium

promethium

noun
pro·​me·​thi·​um | \ prə-ˈmē-thē-əm How to pronounce promethium (audio) \

Medical Definition of promethium

: a radioactive metallic element of the rare-earth group obtained as a fission product of uranium or from neutron-irradiated neodymium symbol Pm — see Chemical Elements Table

More from Merriam-Webster on promethium

Britannica.com: Encyclopedia article about promethium

Comments on promethium

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