Cognomen - Definition

n 1: a familiar name for a person (often a shortened version of
a person's given name); "Joe's mother would not use his
nickname and always called him Joseph"; "Henry's nickname
was Slim" [syn: nickname, moniker, cognomen,
sobriquet, soubriquet, byname]
2: the name used to identify the members of a family (as
distinguished from each member's given name) [syn: surname,
family name, cognomen, last name]