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onium

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adjective oni·um \ˈō-nē-əm\

Definition of onium

  1. :  being or characterized by a usually complex cation

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Origin and Etymology of onium

-onium

-onium

noun suffix oni·um

Definition of -onium

  1. :  an ion having a positive charge hydronium — compare -ium 1b

Origin and Etymology of -onium

New Latin, from ammonium

Medical Dictionary

onium

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adjective oni·um \ˈō-nē-əm\

Medical Definition of onium

  1. :  being or characterized by a usually complex cation onium salts

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