surname

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A name shared in common to identify the members of a family, as distinguished from each member's given name. Also called family name, last name.
2. n. A nickname or epithet added to a person's name.
3. v. To give a surname to.

Century Dictionary and Cyclopedia

1. n. An additional name, frequently descriptive, as in Harold Harefoot; specifically, a name or appellation added to the baptismal or Christian name, and becoming a family name. See to-name. English surnames originally designated occupation, estate, place of residence, or some particular thing or event that related to the person. Thus, William Rufus. or red; Edmund Ironsides; Robert Smith, or the smith; William Turner. Many surnames are formed by adding the word son to the name of the father; thus, from Thomas the son of William we have Thomas Williamson. Surnames as family names were unknown before the middle of the eleventh century, except in rare cases where a family “established a fund for the deliverance of the souls of certain ancestors (Christian names specified) from purgatory.” (Encyc. Brit., X. 144.) The use of surnames made slow progress, and was not entirely established till after the thirteenth century.
2. To name or call by an additional name; give a surname to. See name.

Wiktionary

1. n. A name that indicates to which family a person belongs, normally following that person’s given name(s) in Western culture, and preceding it in Eastern.
2. v. To give a surname.
3. v. To call by a surname.

GNU Webster's 1913

1. n. A name or appellation which is added to, or over and above, the baptismal or Christian name, and becomes a family name.
2. n. An appellation added to the original name; an agnomen.
3. v. To name or call by an appellation added to the original name; to give a surname to.

WordNet 3.0

1. n. the name used to identify the members of a family (as distinguished from each member's given name)