benthonic zone vs benthic division

benthonic zone and benthic division both are nouns.

Word	Noun	Adjective	Verb	Adverb
benthonic zone	Yes	No	No	No
benthic division	Yes	No	No	No

As nouns, benthonic zone and benthic division are synonyms defined as:

benthonic zone and benthic division: a region including the bottom of the sea and the littoral zones

Other synonyms of benthonic zone include benthos.

benthonic zone (noun)	benthic division (noun)
a region including the bottom of the sea and the littoral zones	a region including the bottom of the sea and the littoral zones