benthic division vs benthonic zone

benthic division and benthonic zone both are nouns.

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

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

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

Other synonyms of benthic division include benthos.

benthic division (noun)	benthonic zone (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