litoptern

The story

1. Ancient Greek · derived fromλῑτός“smooth”
2. English todaylitoptern

From modern Latin Litopterna (order name), from Ancient Greek λῑτός (lītós, “smooth”) + πτέρνη (ptérnē, “heel-bone”).

First known use, by meaning

• from 19th c. An extinct hoofed mammal of the order †Litopterna, from the Cenozoic period.