Eohippus

from WordNet (r) 3.0 (2006)

eohippus
    n 1: earliest horse; extinct primitive dog-sized four-toed
         Eocene animal [syn: {eohippus}, {dawn horse}]

from The Collaborative International Dictionary of English v.0.48

Hyracotherium \Hyracotherium\ n.
   An extinct horse genus, formerly called genus {Eohippus}.

   Syn: genus {Hyracotherium}.
        [WordNet 1.5]

from The Collaborative International Dictionary of English v.0.48

eohippus \eo*hip"pus\ ([=e]`[-o]*h[i^]p"p[u^]s), n. [Gr. 'hw`s
   dawn + "ipposhorse.]
   an extinct primitive dog-sized 4-toed Eocene mammal, the
   earliest horse known in the line of descent of the modern
   horse. It is classed in the extinct genus {Hydracotherium}.
   Called also {dawn horse}.

   Syn: dawn horse.
        [WordNet 1.5 +PJC]

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