Such names – like champagne, sherry and port – are called semi-generics, and may be used on labels only in direct conjunction with an appropriate appellation of origin (place in the United States where the grapes were grown) and only on wines that conform to the standard of identity for that class or type.
Names such as champagne, sherry, and port are considered semi-generics. They can only be used on wine labels if they are paired with a specific place of origin (like a region in the United States) and if the wine meets the required standards for its classification.