Cabell has surely a british origin. But in USA it could be an americanization of the Spanish or Italian surname CABELLO or of French CABEL. A surname CABELL could exist also in Spanish region of Catalunya. I an not sure about the meaning of Cabell as a British surname. The spanish Cabello comes from "hair" so it is a nickname. The Italian variant has a locative origin. I ignore the meaning an origin of French Cabel.