Macropinacoid
Pronunciation : Mac`ro*pin"a*coid
Part of Speech : n.
Etymology : [Macro- + pinacoid.] (Crystallog.)
Definition : Defn: One of the two planes of an orthorhombic crystal which are parallel to the vertical and longer lateral (macrodiagonal) axes.
Source : Webster's Unabridged Dictionary, 1913
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