(gemology) Cut flat on the reverse, and with a convex face formed of triangular facets in rows; said of diamonds and other precious stones.

plural of robab

A chart, list, or record of ancestors, to show breeding, especially distinguished breeding. / A person's ancestral history; ancestry, lineage. / (uncountable) Good breeding or ancestry.

A curve to the left or right which immediately curves in the opposite direction, and which is basically S-shaped.