Polished plane (5)
I believe the answer is:
facet
(Other definitions for facet that I've seen before include "side of rock" , "Characteristic" , "Side or surface, diamond or building" , "Side of a cut gem" , "Angle" .)
I believe the answer is:
facet
(Other definitions for facet that I've seen before include "side of rock" , "Characteristic" , "Side or surface, diamond or building" , "Side of a cut gem" , "Angle" .)