terrorist group vs Revolutionary Proletarian Nucleus

terrorist group and Revolutionary Proletarian Nucleus both are nouns.

Word	Noun	Adjective	Verb	Adverb
terrorist group	Yes	No	No	No
Revolutionary Proletarian Nucleus	Yes	No	No	No

terrorist group (noun)	Revolutionary Proletarian Nucleus (noun)
a political movement that uses terror as a weapon to achieve its goals	a clandestine group of leftist extremists who oppose Italy's labor policies and foreign policy; responsible for bombing building in the historic center of Rome from 2000 to 2002