SINCE 1828
onium
adjective
oni·um
| \ ˈō-nē-əm
\
\
Definition of onium
(Entry 1 of 2)
: being or characterized by a usually complex cation
-onium
noun suffixDefinition of -onium (Entry 2 of 2)
: an ion having a positive charge
hydronium
— compare -ium sense 1b
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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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