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Related to Orohippus: mesohippus, Miohippus


n.1.(Paleon.) A genus of American Eocene mammals allied to the horse, but having four toes in front and three behind.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Cami and the Wonder Crew performed "The Case of the Missing Shoe" about Sassy, the orohippus, a small prehistoric relative to the modern horse.
This, in turn, led to very modern proposals for phylogenetic classifications in which reptiles and birds were placed in a single category and the lineage of horses traced to Orohippus with a prediction, quickly fulfilled, of an even older, more generalized type.