What else does sour cream mean?
Light cream homogenized pasteurized and treated with lactic acid culture. This gives it a tart flavor. Light sourcream is made with half-and-half, and has 40 percent less fat than regular. Regular commercial sourcream contains at least 18% milk fat. A nonfat sourcream, which is a thickened product with stabilizers, can also be purchased. (in Cooking Dictionary)
A cream that has been thickened with bacteria to produce lactic acid. It can be used in food or toppings. (in Merlin Dictionary)