1. Cognomen (plural Cognomens or cognomina) Surname

2. Under some circumstances Romans were given an additional cognomen, called an Agnomen.These were the exception to the general rule that cognomina were not complimentary

3. The Cognomen (plural cognomina) formed one of the three parts of the typical Roman name.It was placed after the praenomen and nomen.Originally cognomina were nicknames, but by the time of the Roman Empire they were inherited from father to son.Thus the Cognomen in combination with the nomen functioned as a surname, breaking families into smaller groups than just the nomen alone.

4. Cognomen (Cognomen, plural: cognomina) The third name or Cognomen started to be a nickname or personal name that distinguished individuals within the same gens (the Cognomen does not appear in official documents until around 100 BCE)