terrorist group vs Provisional Irish Republican Army

terrorist group and Provisional Irish Republican Army both are nouns.

Word	Noun	Adjective	Verb	Adverb
terrorist group	Yes	No	No	No
Provisional Irish Republican Army	Yes	No	No	No

terrorist group (noun)	Provisional Irish Republican Army (noun)
a political movement that uses terror as a weapon to achieve its goals	a militant organization of Irish nationalists who used terrorism and guerilla warfare in an effort to drive British forces from Northern Ireland and achieve a united independent Ireland