D defs.my
Entry 1 sense Webster, 1913

Protohippus

· Pro·to·hip·pus · IPA
01 n. A genus of fossil horses from the Lower Pliocene. They had three toes on each foot, the lateral ones being small.
  1. 1.
    A genus of fossil horses from the Lower Pliocene. They had three toes on each foot, the lateral ones being small.(Paleon.)