\Waist"coat\, n.
   (a) A short, sleeveless coat or garment for men, worn
       under the coat, extending no lower than the hips, and
       covering the waist; a vest.
   (b) A garment occasionally worn by women as a part of
       fashionable costume.

Note: The waistcoat was a part of female attire as well as
      male . . . It was only when the waistcoat was worn
      without a gown or upper dress that it was considered
      the mark of a mad or profligate woman. --Nares.

Syn: See {Vest}.