eohippus
Concise Oxford English Dictionary © 2008 Oxford University Press:
eohippus /ˌiːəʊˈhɪpəs/
▶noun (pl. eohippuses) former term for hyracotherium.
– origin C19: from Gk ēōs ‘dawn’ + hippos ‘horse’.
'eohippus' also found in these Oxford entries:

