the calculated use of violence (or 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
the quality of being difficult to do; "he assigned a series of problems of increasing hardness"; "the ruggedness of his exams caused half the class to fail"
the property of being rigid and resistant to pressure; not easily scratched; measured on Mohs scale
high level or degree; the property of being intense
the amount of energy transmitted (as by acoustic or electromagnetic radiation); "he adjusted the intensity of the sound"; "they measured the station's signal strength"