from the GNU version of the Collaborative International Dictionary of English
- n. An extinct Miocene mammal of the Horse family, closely related to the genus Anhithecrium, and having three usable hoofs on each foot.
from The Century Dictionary and Cyclopedia
- n. A genus of fossil perissodactyl ungulates referred to the family Equidœ, occurring in the Miocene strata of North America. These animals were about the size of sheep.
Sorry, no etymologies found.
But what gained greatest attention, especially from ranchers in the west, was his discovery in subsequent years of handsome skeletons of four of the progenitors of the horse: eohippus, mesohippus, miohippus and the crucial, determinative merychippus.