en Asaf, a celebrated rabbi, who, in the fifth century, had a share in the invention of the Hebrew points and accents.

Aaron of Alexandria, a Christian priest and physician, who flourished in Egypt about the year 621. He is the most ancient author who has treated of the small-pox.

Aaron Harischon, a learned rabbi and caraites in the 13th century, wrote an Hebrew grammar, printed at Constantinople 1581; probably the same with Aaron the caraites, who wrote a commentary on the five books of Moses, which is in MS. in the French king's library.