No such word as independant. At least the dictionary doesn't think so. Independant is a misspelling of independent. Independant is a company, Independent is a word.
In any (well designed) experiment, there is one variable that the experimenter can control that affects one (or more) variables. The variable that the experimenter changes is called the independent...
independent variable is the one you control. the dependent variable depends on the indepdendent variable (the results). on the graph independent in on the bottom and dependent is on the side