tragelaphus

plural tragelaphi

1. A fictional animal, half goat, half stag, used by the philosopher Aristotle as an example of something that is knowable even though it does not exist.

   The canathrum, as they call it, is a chair or chariot made of wood, in the shape of a griffin, or tragelaphus, on which the children and young virgins are carried in processions.

   1861, Plutarch, Plutarch's Lives: The Translation Called Dryden's, page 23