independent variable

/ˈɪndəˌpɛndənt ˌvɛriəbəl/

Other forms: independent variables

An independent variable is a term used in math and in experiments. It is a value that you can change, usually indicated by x in a mathematical equation, that does not depend on changes in another value.

Suppose you want to test to see how the amount of water affects a particular type of plant's vertical growth. You use three identical plants, all planted in the same soil, and each getting the same amount of sunlight. The only thing you change is the amount of water each plant gets — that is the independent variable. (The dependent variable would be the height of each plant at the end of the experiment.) In a mathematical function, y = f(x), the x is the independent variable, the value that can be changed to determine what y is.

Definitions of independent variable

1. noun

   (statistics) a variable whose values are independent of changes in the values of other variables
   synonyms: experimental variable

   types:

   factor

   an independent variable in statistics

   type of:

   variable, variable quantity

   a quantity that can assume any of a set of values