What do we call the variable that is measured in an experiment?

The variable that is measured in an experiment is referred to as the dependent variable. This is because its value depends on the changes made to another variable in the experiment, which is known as the independent variable. For instance, if you are studying the effect of sunlight on plant growth, the amount of plant growth (measured by height, biomass, or other metrics) is the dependent variable since it is what you are measuring to see how it responds to the varying levels of sunlight (the independent variable).

In some experiments, there may be controlled or constant variables, which are factors kept unchanged to ensure that the results are due to the manipulation of the independent variable alone. But these controlled or constant variables are not what is being measured. The focus is on the dependent variable, which reflects the outcome of the experiment and provides insight into the relationship between the independent variable and the conditions being tested.