Nomen gentilicium

The Latin nomen gentilicium (generally simplifed as nomen) was the second or family name in the Roman system of naming convension known as the tria nomina which generally consisted of three names but could have a forth added to it. Originally intended to convey ones gens/family or patrilineal ancestry, the mass conversion of non-Latin stock to Roman customs and conventions found the meaning of the nomen gentilicium lost to the flood of adoption of classic Latin names by the non-Latin derived subjects which now flooded the empire via conquest or migration.

Following the Praenomen otherwise known as a 'first name', the nomen could be followed by the embelishing cognomen and more honourary agnomen.

Examples

It can also be said that the Roman nomen conforms most closely to modern European last names due to the lack of consistent methodical use of the second name in modern times. But in many cases last or third names do actually follow the tria nomina by actually being a direct cognomen such as Smith, Thatcher, Weaver, White, Black, Yellow, van Dam, von Albrecht Duchateau, Deschamps and Castellano; while at other times, modern last names can more closely resembles an agnomen such as Brilliant. However, a European tradition wherein a last name conforms more closely to the purpose of the nomen gentilicium are names such as Peterson being Peter's son.

Despite the above modern examples, it must be noted that it is still a frequent modern naming convension for second names to conform to the nomen gentilicium by naming a child's second name in honour of a family member of the same sex.

If we consider a classic Latin example of the tria nomina system such as Julius Caesar, we must note that Julius is not his first name, but rather his nomen representing his father's linage: his first name, or praenomen, is Gaius while Caesar was his cognomen.

Thus when Gaius Julius Caesar adopted his nephew in his will: Gaius Octavius Thurinus ("octavian" being the family name), Octavius changed his nomen gentilicium to "Julius" and accepted the associated cognomen of "Caesar". But Octavian logically kept his first name/praenomen of "Gaius" (which just happened to be the same making the entirety of his name exactly the same as his adopted father and predecessor). It must also be noted at that time Octavian had not yet been honoured with the additional agnomen of "Augustus".

Etymology

Nomen, Latin, literally translates as "Name". But in light of the praenomen, the nomen should be considered as a gens/family name.

See also cognomen and agnomen.