Bucephalus (Ancient Greek: Βουκέφαλος, lit. 'ox-headed', from βους, "ox", and κεφαλή, "head") was a type of branding mark used on horses in ancient Greece. It was one of the three most common, besides Ϻ, San, and Ϙ, Koppa. Those horses marked with a San were called Σαμφόραι, Samphórai; those with a Koppa, Κοππατίαι, Koppatíai; and those with an ox's head, Βουκέφαλοι, Bucéphaloi. This mark was stamped on the horse's buttocks and its harnesses, judging by the scholia on Aristophanes's The Clouds, Hesychius, and other works.