Originally the Dirndl, which is the female form of the traditional German costume, was the dress worn by maids and servants; the word dirn in local Bavarian and Austrian dialects meaning 'maid'. That changed in the 19th century, when the middle classes as well as aristocrats, painters and writers re-discovered nature and roots. They started wearing the servants' outfits during their vacation and adapted them for comfort, luxury and practicality.
The Dirndl consists of a tight waistcoat or Mieder, under which a wide-sleeved blouse with a more or less plunging neckline is worn. The top is combined with a long, full skirt over which an apron is tied. Originally the material was linen, wool in winter. But when re-discovered by the upper classes, Dirndls were fashioned from silk and the apron, waistcoat and even blouse were heavily embroidered. Today, the Dirndl is an accepted and much appreciated fashion item worn even to formal parties, dinners and balls.
During Oktoberfest season, even Lufthansa, the German airline, kitted their flight attendants out with Dirndls to get their passengers on certain routes into the right spirit.