A French term historically used to describe a traditional brown sauce such as Espangnole, which has been simmered and reduced to half of its original volume, resulting in a very thick, intensely flavored mixture. This sauce is then used as a topping for meats and other foods or is used as a base to make other types of sauces. The term "demiglace" today however, is often used in reference to a much wider variety of sauces, such a pan sauces and reduction sauces which all use a brown stock as a base. A demiglace often contains half brown sauce (Espangnole) and half brown stock.
Common sauces in this group include Bordelaise, Chasseur, Chateaubriand, Diable, Diane, Estragon, Lyonnaise, Madère, Madeira, Moscovite, Mushroom, Piquante, Porto, Robert, Romaine, Tarragon, and Zingara.