pachyderm (n.)

1838, from French pachyderme (c. 1600), adopted as a biological term for non-ruminant hoofed quadrupeds 1797 by French naturalist Georges Léopole Chrétien Frédéric Dagobert, Baron Cuvier (1769-1832), from Greek pakhydermos "thick-skinned," from pakhys "thick, large, massive" (see pachy-) + derma "skin" (from PIE root *der- "to split, flay, peel," with derivatives referring to skin and leather). Cuvier's order of Pachydermata is now disused in zoology, but pachyderm remains in common use to describe elephants, rhinoceroses, hippopotamuses, etc. Related: Pachydermal; pachydermic; pachydermatous.