Talk:List of ponies/@comment-3897868-20111030223343/@comment-208.180.10.85-20111103095008

Sabria Alberghetti/Sibsy has been specifically asked this question and confirmed that it's "alicorn" (yes, it's the medieval term for what a unicorn's horn is made of, but that has no bearing on the show). I can dig up a link if you like.