mu·​on·​ium myü-ˈō-nē-əm How to pronounce muonium (audio) -ˈä- How to pronounce muonium (audio)
: a short-lived quasi-atom consisting of an electron and a positive muon

Word History


New Latin

First Known Use

1957, in the meaning defined above

Time Traveler
The first known use of muonium was in 1957

Dictionary Entries Near muonium

Cite this Entry

“Muonium.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2024.

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