mass meeting vs revival

mass meeting and revival both are nouns.

Word	Noun	Adjective	Verb	Adverb
mass meeting	Yes	No	No	No
revival	Yes	No	No	No

As nouns, revival is a hyponym of mass meeting; that is, revival is a word with a more specific, narrower meaning than mass meeting:

Other hyponyms of mass meeting include pep rally, revival meeting.

mass meeting (noun)	revival (noun)
a large gathering of people intended to arouse enthusiasm	bringing again into activity and prominence
	an evangelistic meeting intended to reawaken interest in religion