cult

A small group of spiritually devoted people, usually branching off a larger, well-established organized religion, with specific beliefs and practices that are significantly different from those of the original mother religion. Cults often form around a leader who stresses a particular deity, a sacred ritual, or a unique belief that becomes the focus of unorthodox worship. The word has a negative connotation, as cults are often associated with social deviance, fundamentalism, and forms of psychological manipulation and mind control.