Definition of "social group" [social group]

• A collection of humans or animals, who share certain characteristics, interact with one another, accept expectations and obligations as members of the group, and share a common identity. (noun)

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• "The clergy gives him a model ideal-type or pure case of a social group which, although it draws its postulants from all classes and nations, is free of all complicating overlapping memberships."
• "An eminent sociologist of communication networks, Professor Ron Burt, described opinion leaders as “people on the edge”: opinion leaders have a certain degree of cosmopoliteness in that they bring new ideas from outside their social group to its members."