- A creature with an evil that exceeds the human comprehension.
- In mythology and religion: an unclean spirit.
- A creature that forms the basis of possession.
In media, a daemon is often as a creature with an evil that is unnatural. In such cases persons or even houses can be possessed by a demonic force.
Depending on the religious belief, daemons exist. They do not exists in the protestant-christian belief, but in the catholic-christian belief.