PANIC ATTACK:Acute intense anxiety; symptoms include: dyspnea, sweating, vertigo, palpitations, chest pain, nausea, blurred vision, dread, feeling of loss of mental control, and the feelings of impending death.
AGORAPHOBIA:Overwhelming symptoms of anxiety, often leading to a panic attack. This may occur in a variety of everyday situations (standing in line, eating in public, in crowds of people, on bridges, in tunnels, while driving, or in any situation that a person feels they are unable to escape or to get help, or that they pay suffer from embarassment). People then often have panic attacks, and often avoid phobic situations, even to the point of staying at home for thier entire lives.
***Definitions taken from: Tabers Cyclopedic Medical Dictionary