Merriam-Webster Collegiate Dictionary - perissodactyl

 noun  Etymology: New Latin Perissodactyla, from Greek perissos excessive, odd in number + daktylos finger, toe  Date: circa 1852 any of an order (Perissodactyla) of nonruminant ungulate mammals (as a horse, a tapir, or a rhinoceros) that usually have an odd number of toes, molar teeth with transverse ridges on the grinding surface, and the posterior premolars resembling true molars  • ~ adjective