A hypnotherapist is a person who uses hypnosis as treatment — not as a stage show. They help someone into a very calm, focused state, then use that state to work on a problem: a habit, a fear, pain, or a feeling that is hard to shift when you are fully on guard. The “therapy” half is the point: this is meant to be care, with talk and a plan, not a trick. Though actually, the word sits in a grey place. Some hypnotherapists are also doctors or psychologists; some are not, and places do not all watch this work in the same way. A student should not mix this person up with a stage hypnotist. Same family of words, different job: one is trying to help a body or a feeling; the other is trying to make a room laugh.