phosphonium

noun

phos·​pho·​ni·​um fäs-ˈfō-nē-əm How to pronounce phosphonium (audio)
: a monovalent cation PH4+ analogous to ammonium and derived from phosphine
also : an organic derivative of phosphonium (such as (C2H5)4P+)

Word History

Etymology

New Latin

First Known Use

1859, in the meaning defined above

Time Traveler
The first known use of phosphonium was in 1859

Rhymes for phosphonium

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Browse Nearby Words

phosphonitrile
phosphonium
phosphophyllite
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Cite this Entry

“Phosphonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phosphonium. Accessed 2 May. 2025.

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Medical Definition

phosphonium

noun
phos·​pho·​ni·​um fäs-ˈfō-nē-əm How to pronounce phosphonium (audio)
: a monovalent cation PH4+ analogous to ammonium and derived from phosphine
also : an organic derivative of phosphonium (as (C2H5)4P+)
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