ALYPIUS, one of the seven Greek writers on music whose works are collected and published, with a commentary and explanatory notes, by Meibomius (Antigua Musica Auctores Septem, Amstel., 1652). The time in which he flourished cannot be precisely ascertained. He is said to have written before Euclid and Ptolemy; and Cassiodorus arranges his work, entitled Introduction to Music, between those of Nicomachus and Gaudentius. The work consists solely of a list of symbols of the various scales and modes, and is therefore probably only a fragment.

ALYPIUS of Antioch, a geographer of the 4th century, who was sent by the Emperor Julian into Britain as prefect, and was afterwards commissioned to rebuild the temple of Jerusalem. Among the letters of Julian are two (29 and 30) addressed to Alypius; one inviting him to Rome, the other thanking him for a geographical treatise, which no longer exists.