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Āternĭus, ii, m., a Roman family name: Aternius Fontinalis, a consul A. U. C. 300, Cic. Rep. 2, 35, 60 Mai; from him proceeded the Lex Aternia (or Tarpeia; cf. Fest. s. v. peculatus, p. 237 Müll.): de multā, Gell. 11, 1, 2.