mesothorium

noun

meso·thorium | \ ¦me|zō, ¦mē|, |sō+ \

Definition of mesothorium

: either of two radioactive products intermediate between thorium and radiothorium in the thorium series or a mixture of the two products obtained usually from thorium minerals (as monazite sand) and used as a substitute for radium especially in luminous paints:

a : an isotope of radium

— called also mesothorium 1

—symbol MsTh₁ or Ra²²⁸

b : an isotope of actinium

— called also mesothorium 2

—symbol MsTh₂ or Ac²²⁸

Learn More About mesothorium

Dictionary Entries Near mesothorium

mesothorium

mesotonic system

Statistics for mesothorium

Cite this Entry

“Mesothorium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mesothorium. Accessed 15 Aug. 2022.

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