from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Hyracotherium.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Extinct early Eocene mammal, Hyracotherium leporinum
from the GNU version of the Collaborative International Dictionary of English
- n. 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.
from The Century Dictionary and Cyclopedia
- n. A genus of Eocene horses, representing the oldest known type of the family Equidæ, founded by Marsh (1876) upon remains from the coryphodon-beds of the Lower Eocene of New Mexico, indicating a kind of horse about as large as a fox, with four toes and a half on each fore foot, all incased in horn and forming hoofs, and three hoofed toes on each hind foot.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. earliest horse; extinct primitive dog-sized four-toed Eocene animal
New Latin : eo- + Greek hippos, horse; see ekwo- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)