Roux

n. (Cookery) mixture which is made with flour and fat and then cooked briefly and used as base for sauce or soup

Roux (pronounced like the English word "rue") is a mixture of wheat flour and fat. It is the basis of three of the mother sauces of classical French cooking: Sauce béchamel, Sauce velouté, and Sauce Espagnole.  Butter, vegetable oils, or lard are common fats used. It is used as a base for gravy, other sauces, soufflés, soups and stews.
See more at Wikipedia.org...

Noun
1. a mixture of fat and flour heated and used as a basis for sauces
(hypernym) concoction, mixture, intermixture

adj. red, redhead, ginger

n. sorrel, herbaceous plant with sour-tasting edible leaves; reddish-brown color; reddish brown horse

(n.)
A thickening, made of flour, for soups and gravies.