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 Greater New York, New York, New York City - the largest city in New York State and in the United States; located in southeastern New York at the mouth of the Hudson river; a major financial and cultural center |