Definitions for: Protohippus

[n] Pliocene horse approaching donkeys in size

Webster (1913) Definition: Pro`to*hip"pus, n. [NL., from Gr. ? first + ?
horse.] (Paleon.)
A genus of fossil horses from the Lower Pliocene. They had
three toes on each foot, the lateral ones being small.

See Also: Equus caballus, genus Protohippus, horse