Answer: HOLOCAUST.
During the Second World War, the German Nazis and their allies killed about six million Jews. This methodical, bureaucratic, state-organized operation of persecution and extermination is called the Holocaust. The word "holocaust" is of Greek origin, it means "burnt offering". The Nazis, who came to power in Germany in January 1933 and claimed that the Germans were a "superior race”, considered the Jews to be an “inferior” race, posing a threat to the so—called German racial society.
During the Holocaust, the Nazis also persecuted other groups of people who were considered "inferior": Gypsies, people with mental and physical disabilities, some Slavs (Poles, Russians and others). Communists, socialists, Jehovah's Witnesses and homosexuals were persecuted for political or behavioral reasons.