Demiglace

Demi-glace (from French for "half-frozen") is a type of brown sauce. It is one of the five classic sauces of French cooking and is common to the culinary industry. It is traditionally made by combining equal parts of beef or veal stock and espagnole which is then simmered and reduced by half. The result is a thick, rich sauce. While the demi-glace is suited for meats and other rich dishes, it is more commonly used as a base for other rich sauces and soups.
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Noun
1. sauce Espagnole with extra beef stock simmered down and seasoned with dry wine or sherry
(synonym) demi-glaze
(hypernym) sauce

A thick, intensely flavored, glossy brown sauce that is served with meat, poultry, or fish or used as a base for other sauces. It is made by thickening a rich veal stock, enriching it with diced vegetables, tomato paste and Madiera or sherry, then reducing it until concentrated.