Lewis & Short

Ārētīnus (Ārr-), a, um, adj.,

  1. I. of or pertaining to the town Aretium: testa, Mart. 1, 54: vasa, id. 14, 98; cf. Müll. Etrusk. 2, 244.
  2. II. Subst.: Ārētīni, ōrum, m., the inhabitants of Aretium, Cic. Att. 1, 14, 9; Plin. 3, 5, 8, § 52.