eohippus

noun

eo·​hip·​pus ˌē-ō-ˈhi-pəs 

: any of a genus (Hyracotherium synonym Eohippus) of very small primitive horses from the Lower Eocene having 4-toed forefeet and 3-toed hind feet

called also dawn horse

Word History

Etymology

New Latin, from eo- + Greek hippos horse — more at equine

First Known Use

circa 1879, in the meaning defined above

Kids Definition

eohippus

noun

eo·​hip·​pus ˌē-ō-ˈhip-əs 

: any of a genus of small primitive horses from the Eocene epoch of the western U.S. and Europe with four toes on each front leg and three toes on each rear leg