Definition of the word running dog

The phrase "running dog" is a derogatory term that originated in the socialist and communist propaganda of the Soviet Union during the Cold War. The expression used to refer to a person, usually a suspected collaborator, who was considered by the regime to be acting like a "dog on a leash" and carrying out the orders of a foreign power, as if actively running alongside ("running") such an authority. The term "dog" was meant to suggest that the individual was subservient and without principles, loyally carrying out commands given by a hostile foreign government. The term was used predominantly in propaganda aimed at undermining the suspected collaborator's credibility and characterizing them as acting against the best interests of their own people and nation.