Answer:
Geographical segregation exists whenever the proportions of population rates of two or more populations are not homogenous throughout a defined space. Populations can be considered any plant or animal species, human genders, followers of a certain religion, people of different nationalities, ethnic groups.
Although segregation can be represented in many different ways, it is relatively straightforward to define what is not segregation: a spatial distribution of different categories that is undistinguishable from a uniform random situation (with the same percentages of different categories). We can define segregation as any pattern in the spatial distribution of categories that deviates significantly from a random distribution.