vessignon

from The Collaborative International Dictionary of English v.0.48

Vessicnon \Ves"sic*non\, Vessignon \Ves"sig*non\, n. [F.
   vessigon, fr. L. vesica a bladder, blister.] (Far.)
   A soft swelling on a horse's leg; a windgall.
   [1913 Webster]