Genocide has become an official term used in international relations. The word genocide was not in use before 1944. Before this, in 1941, Winston Churchill described the mass killing of Russian prisoners of war and civilians as "a crime without a name". In that year, a Polish-Jewish lawyer named Raphael Lemkin, described the policies of systematic murder founded by the Nazis as genocide. The word genocide is the combination of the Greek prefix geno- (meaning tribe or race) and caedere (the Latin word for to kill). The word is defined as a specific set of violent crimes that are committed against a certain group with the attempt to remove the entire group from existence or to destroy them.