Have you ever been to a restaurant and seen tomato bisque or lobster bisque on the menu and thought, why not call it soup? Why a bisque? There is a perfectly good explanation.
Bisque is actually of French origin and normally made with seafood, but in the US you can often find bisques that are not made with seafood. It is also quite a thick-yet-smooth soup, because of the way it is prepared. Meanwhile, a soup is simply any liquid paired with vegetable, meats, or other ingredients.
The base of a soup can be anything, but normally starts out with a combination of onions, garlic, celery, and carrots.
However, the base of a bisque usually starts with butter, followed by the base vegetables, and then flour. The flour is used to thicken the soup, which is then thinned out by warm milk.
In a bisque, you will often find more dairy ingredients that contribute a lot of fat and flavor to the dish. Although it ends up being delicious, a bisque is normally not so healthy because of the butter, cream, or milk that is added to it.
Whereas a soup can be completely healthy, especially if you use lots of vegetables and homemade broth or stock.