A dependent variable is a factor in an experiment or study that researchers measure to see how it changes in response to other variables. It is called "dependent" because its value depends on the influence of one or more independent variables. For example, in a study examining how study time affects test scores, the test scores are the dependent variable. In scientific research, identifying the dependent variable is crucial for understanding the relationship between different factors. By manipulating the independent variable, researchers can observe how it impacts the dependent variable, helping to draw conclusions about cause-and-effect relationships.