SINCE 1828
promethium
noun
pro·me·thi·um
| \ prə-ˈmē-thē-əm
\
\
Definition of promethium
: a radioactive metallic element of the rare-earth group obtained as a fission product of uranium or from neutron-irradiated neodymium — see Chemical Elements Table
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More Definitions for promethium
promethium
noun
pro·me·thi·um
| \ prə-ˈmē-thē-əm
\
\
Medical Definition of promethium
: a radioactive metallic element of the rare-earth group obtained as a fission product of uranium or from neutron-irradiated neodymium
—symbol Pm
— see Chemical Elements Table
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