sulfonium

noun

sul·fo·ni·um ˌsəl-ˈfō-nē-əm

: 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

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Browse Nearby Words

sulfonic acid

sulfonium

sulfonyl

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Cite this Entry

Style

“Sulfonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sulfonium. Accessed 3 Feb. 2026.

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Medical Definition

sulfonium

noun

sul·fo·ni·um

variants or chiefly British sulphonium

ˌsəl-ˈfō-nē-əm

: a monovalent group or cation SH₃ or derivative SR₃

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