what makes a soup a bisque

A bisque is a smooth, creamy French-style soup, traditionally made from crustaceans like lobster, crab, or crayfish. It should include a stock made from the shells, a large amount of cream, and a thickening agent made from either finely-ground shells or rice. The meat is typically cooked and used as a topping. The key difference between bisque and regular soup is the way in which cream is used in the dish. Traditional bisque recipes used much more cream than regular soups and the cream was added much earlier in the cooking process to be used as a thickening agent. However, the definition of bisque has expanded to include vegetable bisques, like tomato and butternut squash, and the name "bisque" is often used in a broader sense to describe any thick, smooth soup that is made with cream added either during or after cooking. Unlike bisque, chowder has hearty chunks of meat or vegetables and is almost always thickened with a roux instead of blended ingredients.