Cognomens were third names typically adopted in adulthood by citizens of ancient Rome. This was generally a nickname. According to some ancient Rome wiki "Cognomina often, but not always, referred to a person's appearance or other characteristics". These usually fall into one of several broad categories such as Occupational, Adoptive, Geographical, or Honorific.
They also have a list of some of the most common Cognomens, I will give you the highlights. Note: Each Cognomen typically has a male and a female form. I will just be listing the male form for simplicity.
| Cognomen | Meaning |
|---|---|
| Blaesus | Someone who frequently mispronounces words or has a lisp |
| Caninus | Someone who looks like a dog |
| Cilo | Someone with large lips |
| Habitus | Someone in good physical condition |
| Postumus | Someone born after their fathers death |
Usually a Cognomen was neither self assigned nor assigned by ones parents. It was either inherited from his parents or given by general consensus within the entire community. So say I had very small eyes, small enough to be some distinguishing characteristic, and I have no other particular claim to a greater title, my neighborhood might decide that I am now known as "Lucas Wilson Ocella", where Ocella was typically given to people with small eyes.
I actually think this is pretty fun, but it seems to be a practice thoroughly lost to time. I cant find any modern culture that practices anything similar.
I came to learn about this topic from the ever-interesting Tor's Cabinet of Curiosities video on Myths and Mysteries of the Early Christians. Its great and I recommend you check it out.