The Collaborative International Dictionary of English v.0.48:

Brank \Brank\, Branks \Branks\, n. [Cf. Gael. brangus, brangas,
   a sort of pillory, Ir. brancas halter, or D. pranger fetter.]
   1. A sort of bridle with wooden side pieces. [Scot. & Prov.
      Eng.] --Jamieson.
      [1913 Webster]

   2. A scolding bridle, an instrument formerly used for
      correcting scolding women. It was an iron frame
      surrounding the head and having a triangular piece
      entering the mouth of the scold.
      [1913 Webster]