pos·​i·​tro·​ni·​um | \ ˌpä-zə-ˈtrō-nē-əm How to pronounce positronium (audio) \

Definition of positronium

: 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, "Tantalizing oddity found in exotic atom—but physicists aren’t hyping it," 25 Aug. 2020 That makes positronium an ideal tool with which to look for new physics, Cassidy says. Adrian Cho, Science | AAAS, "Tantalizing oddity found in exotic atom—but physicists aren’t hyping it," 25 Aug. 2020

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

First Known Use of positronium

1945, in the meaning defined above

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The first known use of positronium was in 1945

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Cite this Entry

“Positronium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/positronium. Accessed 1 Mar. 2021.

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