actinium

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noun ac·tin·i·um \ak-ˈti-nē-əm\

Definition of actinium

  1. :  a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende — see element table

Origin and Etymology of actinium

New Latin


First Known Use: 1900


Medical Dictionary

actinium

play
noun ac·tin·i·um \ak-ˈtin-ē-əm\

Medical Definition of actinium

  1. :  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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