terrorist act vs frightening

terrorist act and frightening both are nouns.

Word	Noun	Adjective	Verb	Adverb
terrorist act	Yes	No	No	No
frightening	Yes	Yes	No	No

terrorist act (noun)	frightening (noun)
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	the act of inspiring with fear

terrorist act (adjective)	frightening (adjective)
	causing fear or dread or terror