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Antemnae, ārum (sing. Antemna, Cato. Orig. ap. Prisc. p. 716 P.; Sil. 8, 367), f., a very ancient town of the Sabines, so called from its situation on the river (ante amnem; cf. Interamna) Anio, where it empties into the Tiber, Varr. L. L. 5, § 28 Müll.; Serv. ad Verg. A. 7, 631; cf. Plin. 3, 5, 9, § 68; and Mann. Ital. 1, 662.
Hence, An-temnās, ātis, adj., belonging to Antemnœ; Antemnātes, ium, m., its inhabitants, Liv. 1, 9, 10.