Fascination -
The process of bringing about a hypnotic state by fixing the gaze on a point (typically a small shiny object). Also animal hypnosis.
Fight or Flight -
This is not a threat to get a nervous passenger onto an aeroplane. The fight or flight response represents the two basic choices (supervised by the autonomic nervous system) that we have in response to an alarming development. These instinctive choices were once necessary to our survival in an early predatory environment but are largely obsolete in the modern civilized world. They remain as options that can rarely be taken and severe stress can result from these natural impulses being thwarted. 
Filter Theory -
The theory that the hypnotic state is a result of the mind's attention becoming more and more selective and narrow in it's focus. Whether this is fixation on an external object, the sound of the therapist's voice or fixation on the process of relaxation, the subject can eventually filter out almost everything - including the critical faculty. The mind becomes absorbed in the 'tension' of attention.
Fixation - 
In hypnosis, focusing of the attention at a singular point. In psychoanalysis, the arresting of development at a particular point.
Free Association -
Technique originating in psychoanalysis which is now commonly used in many therapies where the intention is to arrive at memories and ideas that are not available to conscious recollection. Stimulus words are given to which the patient responds with the first word that is evoked. Sometimes used in Hypno-analysis.
Fractionation -
In hypnosis, this is a method of induction (Vogt's fractionation method) where the subject is partially relaxed then roused and asked to recount the sensations experienced. Then the hypnosis/relaxation continues again, often with the therapist 'feeding back' the recounted experience and leading the patient still deeper. The patient is then roused again and his experiences sought, before the hypnosis resumes once again. The process continues until a deep trance state is obtained. 
Freud, Sigmund -
Born in Morovia (1856 - 1939), he studied and spent most of his life in Vienna.
Trained with the emminent neurologist J. M. Charcot and experimented with hypnosis. Freud established the practice of psychoanalysis and spent the rest of his life contributing to it's theory. 
Frigidity -
Lack of sexual desire in a woman. Can have organic or psychological origin. 
Functional disorders -
Thes are problems which affect the physical body but have a psychological origin.
Fusion -
In hypnotic practice this is the process of joining two or more normally disparate concepts, feelings or even memories of experience to form a new experience.
For a simple example - if a patient feels anxiety at the sight of a cat but can clearly remember the feeling of happiness at receiving a special gift then ideo-fusion can be used in hypnosis to connect the image of a cat to the feeling of pleasure at receiving a gift, by having the patient summon both image and sensation at the same time.