sulfonium

noun

sul·​fo·​ni·​um ˌsəl-ˈfō-nē-əm How to pronounce sulfonium (audio)
: a monovalent group or cation SH3 or derivative SR3

Word History

Etymology

New Latin, from sulf- + -onium

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of sulfonium was in 1885

Rhymes for sulfonium

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Browse Nearby Words

sulfonic acid
sulfonium
sulfonyl
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Cite this Entry

“Sulfonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sulfonium. Accessed 4 Jul. 2025.

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Medical Definition

sulfonium

noun
sul·​fo·​ni·​um
variants or chiefly British sulphonium
ˌsəl-ˈfō-nē-əm How to pronounce sulfonium (audio)
: a monovalent group or cation SH3 or derivative SR3
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