cult–noun
1. a particular system of religious worship, esp. with reference to its rites and ceremonies.
2. an instance of great veneration of a person, ideal, or thing, esp. as manifested by a body of admirers: the physical fitness cult.
3. the object of such devotion.
4. a group or sect bound together by veneration of the same thing, person, ideal, etc.
5. Sociology. a group having a sacred ideology and a set of rites centering around their sacred symbols.
6. a religion or sect considered to be false, unorthodox, or extremist, with members often living outside of conventional society under the direction of a charismatic leader.
7. the members of such a religion or sect.
8. any system for treating human sickness that originated by a person usually claiming to have sole insight into the nature of disease, and that employs methods regarded as unorthodox or unscientific.

–adjective
9. of or pertaining to a cult.
10.of, for, or attracting a small group of devotees: a cult movie.

Origin:
1610–20; < L cultus habitation, tilling, refinement, worship, equiv. to cul-, var. s. of colere to inhabit, till, worship + -tus suffix of v. action

Source: Dictionary.com

Here is the list of Cults that has to do with UFO's, guns, inbreeding or thetans; it's here.

* Aum Shinrikyo
* Branch Davidians
* The Church Of The Lamb Of God
* Concerned Christians
* Crocodile Men From Congo
* The Family
* God's Salvation Church
* Heaven's Gate
* House of Yahweh
* Indonesian Witch Hunters
* Jeffrey Lundgren
* Jombola Cult
* Movement for the Restoration of the Ten
* Commandments of God
* The People's Temple
* Scientology
* Solar Temple
* The wh0rg
* Westboro Baptist Church
* World Church of the Creator
* Yahweh Ben Yahweh & The Temple of Love

You can add if you know any other cult. Blessings in Jesus.