Dictionary.com, Cult:
1. A religion or religious sect generally considered to be extremist or false, with its followers often living in an unconventional manner under the guidance of an authoritarian, charismatic leader.
2. The followers of such a religion or sect.
3. A system or community of religious worship and ritual.
4. The formal means of expressing religious reverence; religious ceremony and ritual.
5. A usually nonscientific method or regimen claimed by its originator to have exclusive or exceptional power in curing a particular disease.
6. Obsessive, especially faddish, devotion to or veneration for a person, principle, or thing.
7. The object of such devotion.
8. An exclusive group of persons sharing an esoteric, usually artistic or intellectual interest.
Dictionary.com, Religion:
1. Belief in and reverence for a supernatural power or powers regarded as creator and governor of the universe.
2. A personal or institutionalized system grounded in such belief and worship.
3. The life or condition of a person in a religious order.
4. A set of beliefs, values, and practices based on the teachings of a spiritual leader.
5. A cause, principle, or activity pursued with zeal or conscientious devotion.
I believe the main distinction between religion is this:
A Religion seeks the Truth, serves a God, and results in morality.
A Cult creates a lie, serves self or a man, and results in legalism or lawlessness.