Definition reprinted with permission from Hood, Stephen B. (editor) available from Stuttering Foundation of America: [amazon 093338825X inline]
The apprehension of unpleasantness which arises when the stutterer consciously perceives situations which lead him to anticipate difficulty talking. This fear of difficulty may be and often is intense. It can and sometimes does temporarily paralyze thought and action. Stuttering is usually relatively proportionate to the amount of fear present. Stuttering fears may be of persons, of sounds or words, or of situations such as talking in groups or on the telephone, etc.