(chiefly derogatory) A group, sect or movement following an unorthodox religious or philosophical system of beliefs, especially one in which members remove and exclude themselves from greater society, including family members not part of the cult, and show extreme devotion to a charismatic leader.
(informal) A group of people having an obsession with or intense admiration for a particular activity, idea, person or thing.
The veneration, devotion, and religious rites given to a deity (especially in a historical polytheistic context), or (in a Christian context) to a saint.