An anxiety disorder characterized by a phobia in which the phobic stimulus is a specific type of object (such as spiders), event (such as thunder), activity (such as flying), or situation (such as enclosed spaces), exposure to the phobic stimulus almost invariably triggering an anxiety response or panic attack and being recognized by the afflicted person (if an adolescent or adult) as excessive or irrational but being either avoided or tolerated only with intense anxiety or dread, the avoidance behaviour or anxious anticipation of it interfering significantly with everyday life, occupational or academic performance, or social relationships. Some classifications (including ICD-10) exclude agoraphobia. A comprehensive table of phobias and phobic stimuli is provided in Appendix I at the back of this dictionary. Also called a simple phobia. Compare social phobia.