Roux: is a cooked mixture of flour and fat, traditionally clarified butter. It is the thickening agent of classical French cooking: Butter, vegetable oils, or lard are common fats used. It is used as a thickener for gravy, other sauces, soups and stews. It is typically made equal parts of flour and fat by weight
Slurry: mixture of liquid & insoluble mixture with no heat.
So the difference is one is on the stove and the other one isn't. Heat or No Heat?
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