In sociology, the word sect means a religious group with a high degree of tension with the surrounding society, but whose beliefs are (within the context of that society) largely traditional. A cult, by contrast, also has a high degree of tension with the surrounding society, but its beliefs are (within the context of that society) new and innovative. Sects, in the sociological sense, are generally traditionalist and conservative, seeking to return a religion to its (percieved) religious purity.
In European languages (other than English) the word 'sect' is to refer to a dangerous religious sect, similar to how English-speakers popularly use the word 'cult'.
See also denomination?, ecclesia, and cult.
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