'Periclasite' definitions:

Definition of 'Periclasite'

From: GCIDE

Periclase \Per"i*clase\, Periclasite \Per`i*cla"site\, n. [Pref. peri- + Gr. ? to break.] (Min.) A grayish or dark green mineral, consisting essentially of magnesia (magnesium oxide), occurring in granular forms or in isometric crystals. [1913 Webster]