phosphonium

noun

phos·pho·ni·um fäs-ˈfō-nē-əm

: 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

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Style

“Phosphonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phosphonium. Accessed 22 May. 2025.

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Medical Definition

phosphonium

noun

phos·pho·ni·um fäs-ˈfō-nē-əm

: a monovalent cation PH₄⁺ analogous to ammonium and derived from phosphine

also : an organic derivative of phosphonium (as (C₂H₅)₄P⁺)

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