\Flanch\, n.; pl. {Flanches}. [Prov. E., a projection,
OF. flanche flank. See {Flank}.]
1. A flange. [R.]. (Her.) A bearing consisting of a segment
   of a circle encroaching on the field from the side.

Note: Flanches are always in pairs. A pair of flanches is
      considered one of the subordinaries.