Family name origins & meanings
- Irish (of Norman origin) : habitational name from Cussac in Guienne, France, named with the Romano-Gallic personal name Cūcius or Cussius + the locative suffix -acum. The surname died out in England, but is common in Ireland, where it was imported at the time of the Anglo-Norman invasion in the 12th century. It has been Gaelicized as de Cíosóg.