onium

adjective
oni·um | \ ˈō-nē-əm \

Definition of onium 

(Entry 1 of 2)

: being or characterized by a usually complex cation

-onium

noun suffix

Definition of -onium (Entry 2 of 2)

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

First Known Use of onium

Adjective

1905, in the meaning defined above

History and Etymology for onium

Adjective

-onium

Noun suffix

New Latin, from ammonium

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Dictionary Entries near onium

Oniscus

on it

-onium

onium

onkos

onlap

on-license

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Time Traveler for onium

The first known use of onium was in 1905

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More Definitions for onium

onium

adjective
oni·um | \ ˈō-nē-əm \

Medical Definition of onium 

: being or characterized by a usually complex cation onium salts

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