Discrimination on grounds of race or ethnicity.
The separation of people (geographically, residentially, or in businesses, public transit, etc) into racial or other categories (e.g. religion, sex).
The setting apart in Mendelian inheritance of alleles, such that each parent passes only one allele to its offspring.
The setting apart or separation of things or people, as a natural process, a manner of organizing people that may be voluntary or enforced by law.
Separation from a mass, and gathering about centers or into cavities at hand through cohesive or adhesive attraction or the crystallizing process.
The separation of a pair of chromatids or chromosomes during mitosis and meiosis
The separation of people (geographically, residentially, or in businesses, public transit, etc) into various categories which occurs due to social forces (culture, etc).