terrorist act vs twin towers

terrorist act and twin towers both are nouns.

Word	Noun	Adjective	Verb	Adverb
terrorist act	Yes	No	No	No
twin towers	Yes	No	No	No

terrorist act (noun)	twin towers (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	twin skyscrapers 110 stories high in New York City; built 1368 feet tall in 1970 to 1973; destroyed by a terrorist attack on September 11, 2001