• WordNet 3.6
    • n Ungulata in former classifications a major division of Mammalia comprising all hoofed mammals; now divided into the orders Perissodactyla (odd-toed ungulates) and Artiodactyla (even-toed ungulates)
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Webster's Revised Unabridged Dictionary
    • n. pl Ungulata (Zoöl) An extensive group of mammals including all those that have hoofs. It comprises the Artiodactyla and Perissodactyla.
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Century Dictionary and Cyclopedia
    • ungulata In the Linnean classification, one of the primary divisions, a subclass or super-order, of Mammalia, including all the hoofed quadrupeds, the two Linnean orders Pecora and Belluæ (except the elephant and walrus, which Linnæus placed in Bruta, an order of his Unguiculata). The Ungulata were thus nearly equivalent to the orders Pachydermata, Solidungula, and Ruminantia, and correspond to the modern orders Artiodactyla (the ruminants, pigs, and hippopotamuses) and Perissodactyla (horses, tapirs, and rhinoceroses), together with the Proboscidea and Hyracoidea, and certain fossil groups, as the Ambiypoda. The term, like the correlated Unguiculata, has lapsed from a strict classificatory sense, but is still used as a convenient designation of hoofed quadrupeds collectively or indiscriminately.
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Chambers's Twentieth Century Dictionary
    • n.pl Ungulata (ung-gū-lā′ta) an order of mammals, including (1) the Artiodactyla (with an even number of toes)—e.g. pig, hippopotamus, peccary, camel, and ruminants like cattle, sheep, and deer; (2) the Perissodactyla (with an odd number of toes)—e.g. tapir, rhinoceros, and horse
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Webster's Revised Unabridged Dictionary
NL., fr. L. ungula, hoof
Chambers's Twentieth Century Dictionary
L. unguis, a nail.


In literature:

The field mouse and rabbits are rodentia, the deer ungulata, the kangaroos marsupialia.
"Concerning Animals and Other Matters" by E.H. Aitken, (AKA Edward Hamilton)
Apparently singular as is the elephant in its anatomy, it bears traces of affinity to both Rodentia and Ungulata.
"Natural History of the Mammalia of India and Ceylon" by Robert A. Sterndale
This would make the Ruminants and Ungulata higher than the Quadrumana or the Carnivora.
"Contributions to the Theory of Natural Selection" by Alfred Russel Wallace
The tapetum lucidum is found in Ungulata, Cetacea and Carnivora.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 1" by Various
This is especially marked among the Ungulata.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard