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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



Origin and Etymology of onium

-onium


First Known Use: 1905


-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

play
adjective oni·um \ˈō-nē-əm\

Medical Definition of onium

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




Learn More about onium

  1. Medical Dictionary: Definition of onium


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