[1] : The Collaborative International Dictionary of English v.0.48

pachydermata \pach`yder"mata\
   pa^k`i^d~er"m.at.a, n. pl. nl., fr. gr.
   pachy`dermos thick-skinned; pachy`s thick + de`rma skin.
   zool.
   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.
   1913 webster

Pachydermata >> P Words
Pachydermata, definition of term: Pachydermata
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