ionium

noun

io·​ni·​um ī-ˈō-nē-əm How to pronounce ionium (audio)
: a natural radioactive isotope of thorium having a mass number of 230

Examples of ionium in a Sentence

Recent Examples on the Web Rona set to work isolating a potential new element called ionium. —New York Times, 28 Aug. 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ionium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

ion + -ium; so called from its ionizing action

First Known Use

1907, in the meaning defined above

Time Traveler
The first known use of ionium was in 1907

Dictionary Entries Near ionium

Ionism

ionium

ionization

See More Nearby Entries 

Cite this Entry

“Ionium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ionium. Accessed 29 Sep. 2023.

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Medical Definition

ionium

noun
io·​ni·​um ī-ˈō-nē-əm How to pronounce ionium (audio)
: a natural radioactive isotope of thorium having a mass number of 230

More from Merriam-Webster on ionium

Britannica.com: Encyclopedia article about ionium

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