noun The portion of a person's name that is generally hereditary or treated as an indicator of a person's family, which may be shared with other members of the family, or otherwise derived from their names in some fashion; distinguished from that person's given name(s).
James is my first name, and Smith is my surname.
noun Synonym of epithet, an additional name, particularly those derived from a birthplace, quality, or achievement.
noun Synonym of nickname, an additional name given to a person, place, or thing, a byname.