Aesthesiogenic - 
Sensations of a sensory nature produced by suggestion.
Abreaction -
Occurs when the energy of repressed emotion is brought to consciousness. Catharsis. An exaggerated emotional reaction.
Agnosia - 
Condition where patient is unable to correctly interpret sensory impressions.
Agoraphobia - 
Traditionally defined as the irrational fear of open spaces (from the latin for market place) but is equally often a fear of becoming caught in situation, without means of escape. Paradoxically, this causes withdrawal from that possibility by self confinement.
Alcoholism - 
Addiction to the consumption alcoholic beverages. Alcoholic.
Alexia - 
Inability to recognize the written word as words. This condition is often the result of a brain lesion but can be caused by suggestion.
Algophobia - 
Morbid dread of physical pain.
Allergy - 
A condition (allergic reaction) in which the patient becomes pathologically sensitive to a particular substance or substances.
Amnesia - 
The loss of memory, partial or total, often caused by shock or trauma. Can be due to physical causes, can be caused by suggestion. Sometimes occurs spontaneously after arousal from hypnosis.
Analgesia - 
Reduction or loss of the sensation of pain, can be achieved through hypnosis.
Anchorages -
Frames of reference which people use to make further  judgements.
Anchoring - 
The technique of associating several 'keys' with one fixed point of reference, with the idea of using those keys to later evoke that fix reference. Form of conditioning by association of ideas. Used in NLP and hypnotherapy.
Anaesthesia - 
Loss of sensation and sensitivity, usually due to chemical agent (as with surgery) but is also an important phenomenon of deep hypnosis. Hypnosis can be used as an anaesthetic and many instances of it's usage are on record.
Animal Magnetism -
A term coined by Franz Anton Mesmer (1734 - 1815), who theorized that the effects of 'hypnotism' (which was then to be called 'Mesmerism' after him and before that time known as 'Charming') were due to a fluidic magnetic medium that could be passed from person to person. 
Anorexia Nervosa -
Severe eating disorder, often due to irrational 'body image'. Patients may even hallucinate that they are over weight when close to starvation. Characterized by refusal to maintain body weight at a healthy level.
Anxiety - 
A state of disturbance characterized by fear and worry, which often leads to stress. May be rational or irrational. Responds well to Hypnotherapy.
Aphasia - 
Loss of the ability to speak, usually through non-physical causes and typically a symptom of hysteria. Can also be produced by hypnosis (without the presence of hysteria). Can also be caused by lesions of the brain (cortical).
Aphemia -
Inability to speak certain words.
Arachnaphobia -
Excessive fear of spiders.
Asthma - 
A disorder of the respiratory system which may be of allergic or emotional origin. Where there is an emotional origin the condition can be successfully treated by hypnosis, usually through regression. 
Astraphobia -
Excessive fear of thunder and lightening
Atavistic Theory - 
The theory proposed by Ainslie Meares M.D. to explain the phenomenon of hypnosis. He posited that in hypnosis the higher centres of the brain are systematically closed down and access is gain to parts of the brain which are primitive and pre-rational. Thus hypnosis could be explained as a form of regression to pre-critical functioning.
Attention - 
The ability to sustain ones awareness by focusing it on a particular thing.
Aura - 
The feelings experienced by patients before an attack of epilepsy or migraine headache which warns them of it's imminence.
Auto-Hypnosis - 
Is where an individual has learned the ability to place himself in a state of hypnosis. 
Autogenic - 
Relating to things which originate within the self.
Autonomic -
Self directed, independent.
Autonomic Nervous System -
The nervous system responsible for many of the body's functions, particularly those of the glands, the smooth muscles, respiration and circulation. It is located along the spine and cerebro-spinal system and completely efferent in function. Its is reactive and responsible for the 'Fight or Flight 'response.
Auto-Suggestion - 
Suggestions which originate from within the individual.
Aversion -
A strong dislike of something.
Aversion Therapy -
A form of de-conditioning by associating something unpleasant with a particular behaviour pattern you are trying to eradicate. Typical of behaviour therapy it is used sometimes in hypnosis, for example, to associate a foul thing (like dog excrement or vomit) to the act / taste of smoking, thus helping to de-condition and extinguish the habit.