The Collaborative International Dictionary of English v.0.48:

Strangles \Stran"gles\, n.
   A disease in horses and swine, in which the upper part of the
   throat, or groups of lymphatic glands elsewhere, swells.
   [1913 Webster]

WordNet (r) 3.0 (2006):

strangles
    n 1: an acute bacterial disease of horses characterized by
         inflammation of the mucous membranes [syn: equine
         distemper, strangles]