family name

Noun

 * : a name designating a person as a member of a family.
 * 1)  A given name common within a family or given because of another family member.
 * 1)  A given name common within a family or given because of another family member.

Usage notes
Although and  are both in more common use, family name is sometimes preferred for its lack of cultural and gendered assumptions. In particular, it is more inclusive of East Asian names where the family name is placed first.