sontag

noun1

1. •
   (old-fashioned) A knitted worsted jacket, worn over the waist of a woman's dress.

   • If it had, only think what a scattering of clothing there would have been—skirts, dresses, sontags, double-dresses, shawls, cloaks, hoods, scarfs, veils, and little black strings[…] — 1864