Deux dimensions Définition
Two dimensional or two dimensions is the property of a plane that indicates that motion can take place in two perpendicular directions. Formally, stating that a plane has only two dimensions means that you can find two vectors in the plane for which neither is a multiple of the other. In addition, for any set of three vectors in the plane, one of them can be written as a linear combination of the other two.
“Two Dimensions.” Mathwords, www.mathwords.com/t/two_dimensions.htm.