Maybe you need to talk about the features, such the scale of a map. If so, we could say something like "A map’s scale indicates the relationship between the distances on the map and the actual distances on Earth." (as per National Geographic´s definition.)
That is, a map is a graphic representation of the real world/of part of the earth. The scale of a map is the measure of that representation and the real world/a given part of the earth.
Indeed a map, can be of other planets, etc, but we are going to stick to that definition for the time being. Just for information´s sake.