tho·​ria ˈthȯr-ē-ə How to pronounce thoria (audio)
: a powdery white oxide of thorium ThO2 used especially as a catalyst and in crucibles and refractories and optical glass

Word History


New Latin, from thorium + -a

First Known Use

circa 1841, in the meaning defined above

Time Traveler
The first known use of thoria was circa 1841

Dictionary Entries Near thoria

Cite this Entry

“Thoria.” Dictionary, Merriam-Webster, Accessed 1 Oct. 2023.

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