The term 'independent variable' is a noun phrase; the adjective 'independent' describes the noun 'variable'.
The variable that is changed by experimenter.
The independent variable is freely set by the experimenter, whereas, the dependent variable (presumably) depends of values of the independent variable.
It is the variable you can pick or have control over.
An independent variable is the variable of the experiment that the dependent variable depends on. For example, in an experiment testing the effects of soil quality on a plant's growth, the dependent variable would be the plant's growth and the independent variable would be the quality of the soil.
The independent (or explanatory) variable is changed to test the prediction,
the type of gas used
The independent variable is the one that the experimenter changes, and the dependent variable is the response. For example - if you were doing an experiment about the affect of temperature on growth rates: Temperature = Independent variable Growth = Dependent variable
The independent variable is what you are changing in the experiment to get varied results. The dependent variable is the result of what you have changed. So the dependent variable depends on the independent variable. For example, if you are experimenting with the effect of water on height of a plant, the different amounts of water that you give the plant is the independent variable. The height of the plant that you measure as the result of the water is the dependent variable.
The independent variable.
Changes in the independent variable are independent of changes in any other variable,