The Collaborative International Dictionary of English v.0.48:

Jaunty \Jaun"ty\, a. [Compar. Jauntier; superl. Jauntiest.]
   [Formerly spelt janty, fr. F. gentil. See Gentle, and cf.
   Genty.]
   Airy; showy; finical; hence, characterized by an affected or
   fantastical manner.
   [1913 Webster]