ocean bottom vs ocean floor

ocean bottom and ocean floor both are nouns.

Word	Noun	Adjective	Verb	Adverb
ocean bottom	Yes	No	No	No
ocean floor	Yes	No	No	No

As nouns, ocean bottom and ocean floor are synonyms defined as:

Other synonyms of ocean bottom include Davy Jones's locker, Davy Jones, sea bottom, sea floor, seabed.

ocean bottom (noun)	ocean floor (noun)
the bottom of a sea or ocean	the bottom of a sea or ocean