Pronunciation: (pa"tru-nim'ik),[key] —adj. 1. (of family names) derived from the name of a father or ancestor, esp. by the addition of a suffix or prefix indicating descent.
2. (of a suffix or prefix) indicating descent.
—n. 1. a patronymic name, as Williamson (son of William) or Macdonald (son of Donald).
2. a family name; surname.