Editing Roman naming conventions (section)

====Agnomen====
{{main|Agnomen}}
The proliferation of cognomina in the later centuries of the Empire led some grammarians to classify certain types as ''agnomina''. This class included two main types of cognomen: the ''cognomen ex virtute'', and cognomina that were derived from nomina, to indicate the parentage of Romans who had been adopted from one gens into another. Although these names had existed throughout Roman history, it was only in this late period that they were distinguished from other cognomina.<ref name="Harper's:Nomen"/>

=====''Cognomina ex virtute''=====
The ''cognomen ex virtute'' was a surname derived from some virtuous or heroic episode attributed to the bearer. Roman history is filled with individuals who obtained cognomina as a result of their exploits: [[Aulus Postumius Albus Regillensis]], who commanded the Roman army at the [[Battle of Lake Regillus]]; [[Gaius Marcius Coriolanus]], who captured the city of [[Corioli]]; [[Marcus Valerius Corvus]], who defeated a giant [[Gauls|Gaul]] in single combat, aided by a raven; [[Titus Manlius Torquatus (consul 347 BC)|Titus Manlius Torquatus]], who likewise defeated a Gaulish giant, and took his name from the [[torc|torque]] that he claimed as a prize; [[Scipio Africanus|Publius Cornelius Scipio Africanus]], who carried the [[Second Punic War]] to Africa, and defeated [[Hannibal]].{{fact|date = March 2023}} The examples most often described in scholarship on the subject{{what|date = March 2023}} regarding this class of cognomen come from the period of the Republic, centuries before the concept of the ''agnomen'' was formulated.{{fact|date = March 2023}}

=====Adoptive cognomina=====
{{main|Adoption in ancient Rome}}
Adoption was a common and formal process in Roman culture. Its chief purpose had nothing to do with providing homes for children; it was about ensuring the continuity of family lines that might otherwise become extinct. In early Rome, this was especially important for the patricians, who enjoyed tremendous status and privilege compared with the plebeians. Because few families were admitted to the patriciate after the [[Overthrow of the Roman monarchy|expulsion of the kings]], while the number of plebeians continually grew, the patricians continually struggled to preserve their wealth and influence. A man who had no sons to inherit his property and preserve his family name would adopt one of the younger sons from another family. In time, as the plebeians also acquired wealth and gained access to the offices of the Roman state, they too came to participate in the Roman system of adoption.<ref name="Harper's:Adoption">''[[Harper's Dictionary of Classical Antiquities|Harper's Dictionary of Classical Literature and Antiquities]]'', Second Edition, [[Harry Thurston Peck]], Editor (1897), "Adoption."</ref><ref>''[[Oxford Classical Dictionary]]'', 2nd Ed. (1970), "Adoption."</ref>

Since the primary purpose of adoption was to preserve the name and status of the adopter, an adopted son would usually assume both the praenomen and nomen of his adoptive father, together with any hereditary cognomina, just as an eldest son would have done. However, adoption did not result in the complete abandonment of the adopted son's birth name. The son's original nomen (or occasionally cognomen) would become the basis of a new surname, formed by adding the derivative suffix ''-anus'' or ''-inus'' to the stem. Thus, when a son of [[Lucius Aemilius Paullus Macedonicus|Lucius Aemilius Paullus]] was adopted by [[Publius Cornelius Scipio Africanus (priest)|Publius Cornelius Scipio]], he became [[Scipio Aemilianus|Publius Cornelius Scipio Aemilianus]]; in his will, the [[Roman dictator|dictator]] [[Julius Caesar|Gaius Julius Caesar]] adopted his grandnephew, Gaius Octavius, who became known as [[Augustus|Gaius Julius Caesar Octavianus]].<ref name="OCD:Names"/><ref name="Harper's:Nomen"/><ref name="Harper's:Adoption"/>