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Phaedo or Phaedon, ōnis, m., = Φαίδων, a disciple of Socrates and friend of Plato, after whom Plato has named his dialogue on the immortality of the soul, Cic. N. D. 1, 33, 93; Gell. 2, 18, 1; Lact. 3, 25, 15; Sid. Ep. 2, 9.