animal group vs warren

animal group and warren both are nouns.

Word	Noun	Adjective	Verb	Adverb
animal group	Yes	No	No	No
warren	Yes	No	No	No

As nouns, warren is a hyponym of animal group; that is, warren is a word with a more specific, narrower meaning than animal group:

Other hyponyms of animal group include team, brood, flock, flock, fold, herd, herd, pack, pod, pride, clowder, school, shoal, caste, colony, breed, stock, strain, drove, litter.

animal group (noun)	warren (noun)
a group of animals	a colony of rabbits
	an overcrowded residential area
	a series of connected underground tunnels occupied by rabbits