SINCE 1828
ionium
noun
io·ni·um
| \ ī-ˈō-nē-əm
\
\
Definition of ionium
: a natural radioactive isotope of thorium having a mass number of 230
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More Definitions for ionium
ionium
noun
io·ni·um
| \ ī-ˈō-nē-əm
\
\
Medical Definition of ionium
: a natural radioactive isotope of thorium having a mass number of 230
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