Unicorn, mythological creature resembling a horse or a goat with a one horn on its forehead. The unicorn appeared in early artworks, and it also was referred to in the ancient myths of India and China ( they are also in the bible). 

 The earliest description in Greek literature of a single-horned Creature was by the historian Ctesias ( 400 BCE), who related that the Indian wild ass was the size of a horse, with a white body, purple head, and blue eyes, and on its forehead was a cubit-long horn coloured red at the pointed tip, black in the middle, and white at the base. Those who drank from its horn were thought to be protected from stomach trouble, epilepsy, and poison. It was very fleet of foot and difficult to capture. The actual animal behind Ctesias’s description was probably the Indian rhinoceros.

Certain passages in the holy bible refer to a strong splinded horned creature called re'em. And this word can be transilated to "unicorn"