| Noun | 1. | cognomen - 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"appellation, appellative, designation, denomination - identifying word or words by which someone or something is called and classified or distinguished from others |
| 2. | cognomen - the name used to identify the members of a family (as distinguished from each member's given name) name - a language unit by which a person or thing is known; "his name really is George Washington"; "those are two names for the same thing" maiden name - a woman's surname before marriage |