Which category of spirit is vermouth classified under?

Vermouth is classified as a fortified wine because it is primarily made from wine that has been enhanced with additional alcohol and aromatized with a variety of botanicals, including herbs and spices. The process of fortification involves adding a distilled spirit, usually brandy, to the base wine, which raises the alcohol content and can also enhance its flavor profile.

As a fortified wine, vermouth retains the fundamental characteristics of wine while also displaying the unique flavors imparted by the botanicals used in its production. It is commonly enjoyed as an ingredient in cocktails or served on its own, often as an aperitif, which might explain why it could be associated with other categories like aperitifs and liqueurs. However, the most accurate classification remains fortified wine, as that defines the primary method of its production and alcohol content.