"Alicorn" is the horn of a unicorn. In terms of it referring to a winged unicorn, it did not become widely associated with winged unicorns until 1984 when Piers Anthony popularized it as a portmanteau of the Latin word "ala" (meaning "wing") and obviously "unicorn." Speaking on the matter, Anthony said, “I saw fantasy statuettes in an ad, and one was of a winged unicorn, titled an alicorn, so I figured that was the name and used it. I have not been able to verify it elsewhere.” In fact, "alicorn" originally referred to a horned horse, and eventually gave way to "unicorn," while alicorn came to refer specifically to the horn.