The dependent variable is the variable that is being measured or tested in an experiment. It is the outcome that researchers are interested in measuring, and it "depends" on the independent variable. In other words, the dependent variable is the variable that changes as a result of the manipulation of the independent variable. For example, in an experiment looking at how stress affects heart rate in humans, the dependent variable would be the heart rate. The independent variable would be the stress, which can be directly manipulated in human subjects. In summary, the dependent variable is what is being measured or tested, and it changes in response to the independent variable.