terrorist act vs terrorist group

terrorist act and terrorist group both are nouns.

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

terrorist act (noun)	terrorist group (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	a political movement that uses terror as a weapon to achieve its goals