cognomen
(noun)
noun
1. a familiar name for a person (often a shortened version of a person's given name)
Similar word(s): byname, moniker, nickname, sobriquet, soubriquet
Definition categories: communication, appellation, appellative, denomination, designation
2. the name used to identify the members of a family (as distinguished from each member's given name)
Similar word(s): surname
Definition categories: communication, name