actinium

noun ac·tin·i·um \ ak-ˈti-nē-əm \

Definition of actinium

:a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende — see Chemical Elements Table

Origin and Etymology of actinium

New Latin


Medical Dictionary

actinium

noun ac·tin·i·um \ ak-ˈtin-ē-əm \

medical Definition of actinium

:a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende symbol Ac — see Chemical Elements Table

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