periclase

noun peri·clase \ ˈperəˌklās , -āz \

variants: or periclasite \ˌperəˈklā|ˌsīt, pəˈriklə|, |ˌzīt\

Definition of periclase

plural -s

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

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Origin and Etymology of periclase

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)