(adjective) : September, bris, m.septem; as, October, Novem-ber, Decem-ber; cf. Varr. L. L. 6, § 34 Müll.
* The seventh month of the Roman year, reckoning from March, i. e. our ninth, September (consisting, as now, of thirty days); usually with mensis: mense Septembri,Cic. Att. 1, 1, 2; Suet. Aug. 31; 35; id. Tib. 26; id. Calig. 15; id. Dom. 13 fin.—Without mensis, Aus. Ecl. de Mens. Monos. 9; so id. ib. Dist. 18; id. ib. Quot. Kal. 8 al.—As , with other substantives, of September, September-: Kalendis Septembribus,Cic. Fam. 14, 22; XIX. Kal. Septemb. (Aug. 14); XIII. Kal. Septemb. (Aug. 20), etc.... pridie Kal. Septemb. (Aug. 31) ... Calendis Septemb.... quarto Nonas Septemb. (Sept. 2) ... Non. Septemb. (Sept. 5) ... VII. Idus Septemb. (Sept. 7) ... tertio Idus Septembris (Sept. 11) ... Id. Sept. (Sept. 13), Col. 11, 2, 57 sq.: Idibus Septembribus,Liv. 7, 3; so Suet. Caes. 83: Septembribus horis, in the (unhealthy) time of September, Hor. Ep. 1, 16, 16 Schneid.

Male Personal name
Confirmed occurences in the Roman Empire:

• M. Caecilius September (Masc), ref: XVI 35 | PIR ID3169