Atlantic Ocean vs North Sea

Atlantic Ocean and North Sea both are nouns.

Word	Noun	Adjective	Verb	Adverb
Atlantic Ocean	Yes	No	No	No
North Sea	Yes	No	No	No

Atlantic Ocean (noun)	North Sea (noun)
the 2nd largest ocean; separates North and South America on the west from Europe and Africa on the east	an arm of the North Atlantic between the British Isles and Scandinavia; oil was discovered under the North Sea in 1970