Answer: A point in the plane.
Explanation:
In this case, we only have one data, the pair (x,y). This pair only can define a "point" that is located in the plane, where the point, along with the line and the plane, are the fundamental objects in the geometry.
In some notations, the pair (x,y) also can denote a vector that has an origin in the point (0,0) but this is not the case, because this does not refer to a geometric term.