Gaius Arrius Antoninus was a Roman senator and jurist active in the last half of the second century AD, who held a number of offices in the emperor's service. The date when he was suffect consul is not attested, but has been estimated to be around AD 173.[1] Edward Champlin includes him, along with Gaius Aufidius Victorinus and Tiberius Claudius Julianus, as "marked out as a special intimate of Fronto's." Champlin notes that while Victorinus received five of the surviving letters of the rhetor Fronto, "as the beloved pupil and son-in-law", Antoninus received four, taking "the place of Fronto's son."[2]
He is thought to have a son, Gaius Arrius Quadratus, praetor of Dacia, Ulpia Traiana Sarmizegetusa.[citation needed]
Despite the similarity in names, Antoninus was not related to Gnaeus Arrius Antoninus, the maternal grandfather of the emperor Marcus Aurelius;[3] Géza Alföldy notes an inscription attests that his father was a leading citizen of Cirta in North Africa.[4]