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 element table

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July 29, 2015
indomitable Hear it
incapable of being subdued or conquered
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