Source : Webster's Revised Unabridged Dictionary (1913)

Kirtle \Kir"tle\, n. [OE. kirtel, curtel, AS. cyrtel; skin to
   Icel. kyrtill, Sw. kjortel, Dan. kiortel, kiole.]
   A garment varying in form and use at different times, and
   worn doth by men and women.

         Wearing her Norman car, and her kirtle of blue.
                                                  --Longfellow.

   Note: The term is still retained in the provinces, in the
         sense of `` an outer petticoat.'' --Halliwell.

Source : WordNet®

kirtle
     n 1: a garment resembling a tunic that was worn by men in the
          Middle Ages
     2: a long dress worn by women