PRISCIANUS, an eminent grammarian, born at Cæsarea, taught at Constantinople with great reputation about the year 325. Laurentius Valla calls Priscian, Donatus, and Servius, triumviri in re grammatica; and thinks none of the ancients who wrote after them, fit to be mentioned with them. He composed a work De arte grammatica, which was first printed by Aldus at Venice in 1476; and another De naturalibus questionibus, which he dedicated to Chosroes king of Persia: beside which he translated Dionysius's description of the world into Latin verse. A person who writes false Latin is proverbially said to "break Priscian's head."