• Webster's Revised Unabridged Dictionary
    • n. pl Pachydermata păk`ĭ*dẽr"mȧ*tȧ (Zoöl) A group of hoofed mammals distinguished for the thickness of their skins, including the elephant, hippopotamus, rhinoceros, tapir, horse, and hog; the pachyderms. It is now considered an artificial group.
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Century Dictionary and Cyclopedia
    • pachydermata The non-ruminant ungulate mammals, or hoofed quadrupeds which do not chew the cud; in Cuvier's classification, the seventh order of Mammalia, divided into Proboscidea, Ordinaria, and Solidungula. The order contained the elephants, hippopotamuses, swine, rhinoceroses, hyraxes, tapirs, horses, etc., corresponding to some extent with the Belluæ of Linnæus. It is disused, its components now forming the orders Proboscidea, Hyracoidea, the perissodactyl suborder of Ungulata, and a few of the artiodactyls. Also called Jumenta.
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Webster's Revised Unabridged Dictionary
NL., fr. Gr. pachy`dermos thick-skinned; pachy`s thick + de`rma skin


In literature:

PACHYDERMATA, hoofed animals with thick skins and non-ruminant, such as the elephant and the hog.
"The Nuttall Encyclopaedia" by Edited by Rev. James Wood
It and the peccary are the only two Pachydermata, or thick-skinned animals, indigenous to the southern continent.
"The Western World" by W.H.G. Kingston
A fossil extinct quadruped belonging to the order Pachydermata, resembling a pig.
"Principles of Geology" by Charles Lyell