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Mūsōnĭus, i, m., a famous Stoic philosopher of the time of Tiberius, Vespasian, and Titus, teacher of Epictetus, Tac. A. 14, 59; Plin. Ep. 3, 11, 5; Amm. 27, 9, 6; Gell. 16, 1, 1.
Hence, Mūsōnĭānus, a, um, adj., of or belonging to Musonius, Musonian, Amm. 15, 13, 1; 16, 9, 2.