The Collaborative International Dictionary of English v.0.48:

Bandeau \Ban*deau"\ (b[a^]n*d[=o]"; b[a^]n"d[=o]), n.; pl.
   Bandeaux (b[a^]n*d[=o]z"). [F.]
   A narrow band or fillet, as for the hair, part of a
   headdress, etc.
   [Webster 1913 Suppl.]

         Around the edge of this cap was a stiff bandeau of
         leather.                                 --Sir W.
                                                  Scott.
   [1913 Webster] Bandlet
   Bandelet