Carmeninius Vetus received his polyonomous name from his father, Lucius Calventius Vetus Carminius, suffect consul in 51. This arose, according to Olli Salomies, apparently because "he was originally a Carminius (Vetus?) and that he was adopted by a L. Calventius."Salomies, Adoptive and polyonymous nomenclature in the Roman Empire, (Helsinki: Societas Scientiarum Fennica, 1992), p. 25 Vetus had a brother, Lucius Carminius Lusitanicus, suffect consul in 81.
