Many only think of the mythical creature when they here the term "unicorn". However when one takes the time to research it they find this is a name used to identify the single horned rhino.
A extinct breed of this is called "Elasmotherium Sibiricum" (above).
A living example of this single horned rhino (water ox) is known as "Rhinoceros Unicornis" (unicorn)/ (above)