UNICORN

A mythical beast resembling a horse or deer with a single, straight, spiraled horn projecting from its forehead.

In various Bible translations, used to render the Latin unicornis or rhinoceros (representing Hebrew רְאֵם): a reem or wild ox.

Any large beetle having a horn-like prominence on the head or prothorax, especially the Hercules beetle, Dynastes tityus.

(sexual slang) To participate in a sexual threesome as a bisexual addition to an established heterosexual couple.

To exceed a valuation of one billion U.S. dollars, while solely backed by venture capitalists.