actinide series


Definition of actinide series

: a series of heavy radioactive metallic elements of increasing atomic number considered to be analogous to the lanthanide series and to begin with actinium (89) or thorium (90) and end with element of atomic number 103 — compare actinium series, periodic table

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First Known Use of actinide series

1945, in the meaning defined above

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The first known use of actinide series was in 1945

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