Outgroup may refer to:
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Outgroup (cladistics)
In cladistics or phylogenetics, an outgroup is a more distantly related group of organisms that serves as a reference group when determining the evolutionary relationships of the ingroup, the set of organisms under study, and is distinct from soci ...
, an evolutionary-history concept
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Outgroup (sociology)
In sociology and social psychology, an in-group is a social group to which a person psychologically identifies as being a member. By contrast, an out-group is a social group with which an individual does not identify. People may for example ide ...
, a social group
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