Word Study
eohippus
CIDE DICTIONARY
eohippus, 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 . [WordNet 1.5]
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