Etymology
Advertisement

cognomen (n.)

1754, "a distinguishing name;" 1809, "a surname;" from Latin, from assimilated form of com "with, together" (see com-) + (g)nomen "name" (from PIE root *no-men- "name"). The last of the three names by which a Roman citizen was known (Caius Julius Csar, Marcus Tullius Cicero).

Others are reading

Advertisement
Advertisement
Definitions of cognomen

cognomen (n.)
a familiar name for a person (often a shortened version of a person's given name);
Synonyms: nickname / moniker / sobriquet / soubriquet / byname
cognomen (n.)
the name used to identify the members of a family (as distinguished from each member's given name);
Synonyms: surname / family name / last name
From wordnet.princeton.edu