Octavius (praenomen)

Octavius is a Latin praenomen, or personal name. It was never particularly common at Rome, but may have been used more frequently in the countryside. The feminine form is Octavia. The name gave rise to the patronymic gens Octavia, and perhaps also to gens Otacilia. A late inscription gives the abbreviation Oct.

The praenomen Octavius is best known from Octavius Mamilius, the prince of Tusculum, and son-in-law of Lucius Tarquinius Superbus, the seventh and last king of Rome, who was slain by Titus Herminius at the Battle of Lake Regillus about 498 B.C. Members of gens Mamilia afterward came to Rome, and the name must have been used by the ancestors of the Octavii and perhaps the Octacilii, but examples of the praenomen are scarce. It must have been used from on occasion throughout the Roman Republic and well into imperial times. The name was used by gens Maecia, and an Octavia Valeria Vera lived at Ticinum in the 2nd or 3rd century; and indeed, the name has survived to the present day.

The Latin word for eighth is octavus, and this is the root of the praenomen, although as a name it is nearly always found with an "-i stem," Octavius or Octavia instead of Octavus or Octava. This is also the case with other praenomina, including Marcia and Titia, the feminine forms of Marcus and Titus.

Octavius falls into the same class as the masculine praenomina Quintus, Sextus, Septimus, Nonus, and Decimus, as well as the feminine names Prima, Secunda, Tertia, Quarta, Quinta, Sexta, Septima, Nona, and Decima. It was probably given to an eighth child, an eighth son, or an eighth daughter. However, it has also been postulated that such names could refer to the month of the year in which a child was born. This explanation does not seem to account for the relative scarcity of Septimus, Octavius, or Nonus. But because parents were generally free to choose whichever name they happened to like, irrespective of its meaning, it may be that such names were given for both of these reasons.

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