* Hypnosis: A state of altered consciousness characterized by focused attention and increased suggestibility.
* Hypnotic: Something that induces sleep or trance-like states.
* Hypnotist: A person who practices hypnosis.
* Hypnopedia: Learning while asleep (though this is not scientifically proven to be effective).
* Hypnopath: A person suffering from a sleep disorder.
* Hypnoses: The plural of hypnosis.
* Hypnologist: A specialist in the study and treatment of sleep disorders.
These words are all related to the concept of sleep and its associated phenomena.