positronium

noun
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

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 18 Feb. 2020.

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Britannica.com: Encyclopedia article about positronium

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