anxiety disorder

n. behavior or chronic condition characterized by persistent worry and extreme anxiety over different activities and events having physical symptoms of palpitations and sweating and feelings of stress

Anxiety disorder is a blanket term covering several different forms of abnormal, pathological anxiety, fears, phobias. It describes nervous system disorders as irrational or illogical worry not based on fact. Anxiety and fear are ubiquitous emotions. The terms anxiety and fear have specific scientific meanings, but common usage has made them interchangeable. For example, a phobia is a kind of anxiety that is also defined in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV-TR) as a "persistent or irrational fear." Fear is defined as an emotional and physiological response to a recognized external threat (eg, a runaway car or an impending crash in an airplane). Anxiety is an unpleasant emotional state, the sources of which are less readily identified. It is frequently accompanied by physiological symptoms that may lead to fatigue or even exhaustion. Because fear of recognized threats causes similar unpleasant mental and physical changes, patients use the terms fear and anxiety interchangeably. Thus, there is little need to strive to differentiate anxiety from fear. However, distinguishing among different anxiety disorders is important, since accurate diagnosis is more likely to result in effective treatment and a better prognosis.
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Anxiety disorder n. Any of various psychiatric disorders in which anxiety is either the primary disturbance or is the result of confronting a feared [more]Anxiety disorder - Community and Resources

Noun
1. a cover term for a variety of mental disorders in which severe anxiety is a salient symptom
(hypernym) mental disorder, mental disturbance, disturbance, psychological disorder, folie
(hyponym) generalized anxiety disorder, GAD, anxiety reaction

noun
state of being very worried and afraid
anxiety disorder = mental disorder (such as a phobia) where the patient is very worried and afraid