radioactinium

noun
ra·​dio·​actinium | \ "+ \

Definition of radioactinium

: the radioactive isotope of thorium of mass number 227 formed by disintegration of actinium symbol RdAc or Th227 — see actinium series

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History and Etymology for radioactinium

New Latin, from radio- + actinium

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Statistics for radioactinium

Cite this Entry

“Radioactinium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radioactinium. Accessed 15 Jun. 2021.

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