"Or, a chief gules, indented. INDENTED. A serrated figure, much smaller than the dancette." -Hall, 1862
The word concave means curving in or hollowed inward.
A line indented for dividing a field. "Escutcheons that have more than one tincture are divided by lines…
The Or Ordinary is a bend indented.
The Per Bend Indented is in azure (blue) and argent (silver) colors.