What is negative feedback in the body?
A form of homeostasis...
Negative feedback basically refers to the body's ability to counteract a change in the body by releasing hormones. Usually, negative feedback is referred to the body trying to lessen a substance or hormone. It actually exists in a "loop". Here is one such example:
Another example is body temperature control. When the temperature in the body gets too high, we start sweating to reduce the temperature to normal again. When we get too cold, we start shivering to warm up ourselves again.