Noun | 1. | ![]() act of terrorism, terrorism, terrorist act - the calculated use of violence (or the threat of violence) against civilians in order to attain goals that are political or religious or ideological in nature; this is done through intimidation or coercion or instilling fear klavern - a local unit of the Ku Klux Klan South - the region of the United States lying to the south of the Mason-Dixon line grand dragon - a high ranking person in the Ku Klux Klan |