Kincsem, (foaled 1874), European racehorse whose total of 54 victories (1876–79) without defeat was into the 1980s the best unbeaten record in the history of flat (Thoroughbred) racing. A mare sired by Cambuscan out of Water Nymph (both English-bred horses), she was foaled in Hungary and raced in Austria, England, France, and Germany, as well as in her native country.