An emotional wound or shock often having long-lasting effects.
In psychiatry, a painful emotional experience or shock with lasting psychic consequences; in medicine, any physical damage or injury.
In psychiatric terms a trauma may have long-lasting effects, during which an insignificant event triggers the original distress. A person then may have difficulties in normal life, such as in establishing relationships or sleeping. In psychological terms this is known as post-traumatic stress disorder. It can be treated by psychotherapy.