plural -s
: a dark gray porous rock consisting of trachyandesite containing phenocrysts of andesine, sanidine, diopside, and a little olivine in a trachytic groundmass of sanidine, a little oligoclase, much diopside, and magnetite

Word History


German arsoit, from Arso, town on the island of Ischia, Italy + German -it -ite

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Dictionary Entries Near arsoite

Cite this Entry

“Arsoite.” Dictionary, Merriam-Webster, Accessed 18 Jul. 2024.

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