mesothorium

noun

meso·​thorium
¦me|zō,
¦mē|,
|sō+
: 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

Word History

Etymology

New Latin, from mes- + thorium

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Cite this Entry

“Mesothorium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mesothorium. Accessed 19 Apr. 2024.

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