What is "ausci"

The Ausci were an Aquitani pre- Roman tribe settled in what today is southwestern France, in the city of Elimberrum or Eliberris (from Basque, hiri: "city" and berri: "new"), present-day Auch in the French department of Gers. The Ausci spoke a form or dialect of the Aquitanian language, a precursor of the Basque language.