What is "biancone"

Biancone is the name or a synonym of several French and Italian grape varieties including:

• Biancone Gentile, also known as Biancu Gentile, on the island of Corsica
• Biancone blanc, also known as Biancone di Portoferraio on the island of Elba
• Biancone dell'Antella
• Biancone della Pieve
• Mostosa, an Italian variety also known as Biancone
• Rollo (grape), an Italian variety also known as Biancone
• Trebbiano, an Italian variety also known as Biancone