Displacement is the redirection of anxiety onto a substitute or "safer" target. The redirected energy, often anger, cannot be discharged in the most logical way, so it must find another way to be released.
The classic example is the frustrated worker who feels victimized by his boss but cannot express his anger directly at his supervisor. Instead, he finds a safer target and yells at his family when he arrives home. According to Freud, the man does not intentionally displace his anger and frustration on his family, but unconsciously does so because he finds the relationships of his family "safer." Venting his frustration at home will minimize consequences arising from his actions, were he to express his anger on the job.