ALBON, or OVON, a king of Hungary. He married the sister of Stephen I. and was elected king on the deposition of Peter in 1041. The emperor Henry III. preparing to reinstate Peter on the throne, Aba made an incursion into his dominions, and returned loaded with booty; but was next year obliged to make restitution, by paying a large sum in order to prevent a threatened invasion from the emperor. He indulged in great familiarity with the lower class of the people; on account of which, and his severity to their order, he became universally odious to the nobility. The fugitive nobles, aided by the emperor, excited a revolt against him. After a bloody battle, Aba was put to flight; and was murdered by his own soldiers in 1044, having reigned three years.

ABACÆNUM, in Ancient Geography, a town of Sicily, whose ruins are supposed to be those lying near Trippi, a citadel on a high and steep mountain not far from Messina. The inhabitants were called Abacænini.