The removal from consciousness of forbidden thoughts and wishes. The removed content does not vanish and it remains as potent as ever, fermenting in one’s unconscious. It is liable to create inner conflicts and anxiety and provoke other defense mechanisms to cope with these.
While blackouts are alcohol, repressions are psychologically induced, deluding times of forgetfulness. All people, of course, have repressions. When a given memory is so unwanted, so shameful or painful, an automatic system turns it off for us without our being aware that it is working for us. As the alcoholism progresses, repressions become more intense.