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septemdĕcim, v. septendecim.
septendĕcim (less correctly sep-temdĕcim; v. the letter M), num. adj. [septem-decem], seventeen: septendecim populi, Cic. Verr. 2, 5, 47, § 124; id. Phil. 5, 7, 19 (B. and K. XVII.); Liv. 38, 51; Tac. A. 13, 6 al.; so freq. in Liv., acc. to Prisc. p. 1170 P.; cf. Drak. on Liv. 29, 37, and 10, 12; yet in Liv., as well as in other authors, the MSS. have for the most part the numerals XVII. instead of the word.
For septendecim we have septem decem, Cic. Agr. 2, 7, 16 (B. and K. XVII.); Liv. 24, 49, 1; 25, 5, 8; 27, 11, 15: septem et decem, Plaut. Cist. 4, 2, 89: decem et septem, Liv. 28, 4, 6; 33, 21; 40, 40, 11; Plin. Ep. 2, 17, 2; Val. Max. 5, 6, 4; Dig. 3, 1, 1, § 3: decem septemque, Nep. Cato, 1, 2: decem septem, Liv. 24, 15, 2, acc. to the best MSS.; cf. also Prisc. 1. 1.: SEPTEMQVE DECEMQVE, Inscr. Neap. 6587; C. I. L. 5, 958; acc. to Charis. p. 55 P., septendecim was in use only among the antiqui; cf. Neue, Formenl. 2, p. 151 sq.