What is the meaning of the word actinium?
actinium. noun. ac·tin·i·um ak-ˈtin-ē-əm. : a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende.
actinium. noun. ac·tin·i·um ak-ˈtin-ē-əm. : a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende.