eohippus
/ˌiːəʊˈhɪpəs
/noun (plural eohippuses)
Former term for hyracotherium.‘We suspect that an intermediate version of the horse between eohippus and equus probably did exist, and that fossils of these intermediates probably do, in fact, exist.’
Origin
Late 19th century: from Greek ēōs 'dawn' + hippos 'horse'.