plural -s
: a mineral CuSiO2(OH)2 consisting of hydrous copper silicate and occurring in emerald-green crystals and massive (hardness 5, specific gravity 3.47)

Word History


French, probably from Late Greek dioptos transparent (from Greek dia- + optos visible, from opsesthai to be going to see) + French -ase (as in euclase)

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Dictionary Entries Near dioptase

Cite this Entry

“Dioptase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dioptase. Accessed 25 May. 2024.

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