'Roux' definitions:

Definition of 'roux'

From: WordNet
noun
A mixture of fat and flour heated and used as a basis for sauces

Definition of 'Roux'

From: GCIDE
  • Roux \Roux\, n. [F. beurre roux brown butter.] (Cookery) A thickening, made of flour, for soups and gravies. [1913 Webster]