Pachydermata n. pl. : A group of hoofed mammals distinguished for the thickness of their skins, including the elephant, hippopotamus, rhinoceros, tapir, horse, and hog. It is now considered an artificial group.

Example:


Taxonomy
Pachydermata, free encyclopedia, the mammals, pachyderm, history, search, Unsourced, skin, one time, systematists, grouping, unrelated, recognised, exception, Ungulates, anatomical, characters, affinities.

Defination from the web: