pos·​i·​tro·​ni·​um ˌpä-zə-ˈtrō-nē-əm How to pronounce positronium (audio)
: a short-lived system that consists of a positron and an electron bound together and is suggestive of a hydrogen atom

Examples of positronium in a Sentence

Recent Examples on the Web For example, in the 1990s physicists thought, essentially, that positronium didn’t live as long as predicted. Adrian Cho, Science | AAAS, 25 Aug. 2020 That makes positronium an ideal tool with which to look for new physics, Cassidy says. Adrian Cho, Science | AAAS, 25 Aug. 2020

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

Word History

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of positronium was in 1945

Dictionary Entries Near positronium

Cite this Entry

“Positronium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/positronium. Accessed 6 Dec. 2023.

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