actinide series

noun

: 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

Word History

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of actinide series was in 1945

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Cite this Entry

“Actinide series.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinide%20series. Accessed 24 Jul. 2024.

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