inundation vs flock

inundation and flock both are nouns.

Word	Noun	Adjective	Verb	Adverb
inundation	Yes	No	No	No
flock	Yes	No	Yes	No

As nouns, flock is a hypernym of inundation; that is, flock is a word with a broader meaning than inundation:

inundation (noun)	flock (noun)
the rising of a body of water and its overflowing onto normally dry land	a group of birds
an overwhelming number or amount	a group of sheep or goats
	a church congregation guided by a pastor
	an orderly crowd
	(often followed by `of') a large number or amount or extent

inundation (verb)	flock (verb)
	come together as in a cluster or flock
	move as a crowd or in a group