Aelius Herodianus (Greek: Αἴλιος Ἡρωδιανός) or Herodian (fl. 2nd century CE) was one of the most celebrated grammarians of Greco-Roman antiquity. He is usually known as Herodian except when there is a danger of confusion with the historian also named Herodian. Herodian was the son of Apollonius Dyscolus and was born in Alexandria. From there he seems to have moved to Rome, where he gained the favour of the emperor Marcus Aurelius, to whom he dedicated a work on prosody.