Cult
Part of speech: adjective
Definition: Of, or relating to a cult. Enjoyed by a small, loyal group.
Part of speech: noun
Definition: A group or doctrine with religious, philosophical or cultural identity sometimes viewed as a sect, often existent on the margins of society and/or exploitative towards its members. Devotion to a saint.
Example sentence: But 'Memento' was so successful, such a huge cult hit, almost on the scale of a large film. If that had happened, with all the acclaim, before the next job, I'd have found it very difficult to figure out what to do next.
Fad
Part of speech: noun
Definition: A phenomenon that becomes popular for a very short time.
Example sentence: I do suspect that privacy was a passing fad.