Hypnotic remains related to sleep. It is also used to refer to sleeping pills.

Hypnopompic refers to something that occurs at the end of sleep.

A hypnopompic hallucination is a crazy image or sound experienced at the moment of waking.

A hypnagogic jerk (I think we’ve all experienced this disturbing sensation) is when the body suddenly jerks when a person is falling asleep.

Hypnagogic images are very crazy types of images that occur at sleep’s beginning: most intense when the sleep session begins with an REM stage (as often is the case with narcolepsy).

Hypnagogic means something which occurs at the beginning of sleep.