variants or periclasite
plural -s
: native magnesia MgO in granular forms or isometric crystals (hardness 6, specific gravity 3.67–3.90)

Word History


periclase from German periklas, modification of Italian periclasia, from Greek periklasis act of twisting or breaking around (from periklan to twist around, break around—from peri- + klan to break—+ -sis) + -ia -y (from Latin); periclasite from periclase + -ite (lame)

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Dictionary Entries Near periclase

Cite this Entry

“Periclase.” Dictionary, Merriam-Webster, Accessed 12 Apr. 2024.

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