Hypnosis is a focus and imagination. Usually, relaxation is part of the clinical experience, but it's really a secondary benefit.
The Scottish surgeon James Braid coined the term "hypnotism", then later he sought to change the name to ""monoideism"", but the name had already caught on. He changed his mind on the name because as he researched it, he found that "hypnosis" had a lot less to do with "hypno" (Greek for "sleep") than it did with focus.
In a hypnotic trance, the noise in your mind stops and you are able to focus with crystalline clarity on the voice of the hypnotist and the suggestions being made.