suboceanic vs marine

suboceanic is not a noun while marine is a noun.

Word	Noun	Adjective	Verb	Adverb
suboceanic	No	Yes	No	No
marine	Yes	Yes	No	No

suboceanic (noun)	marine (noun)
	a soldier who serves both on shipboard and on land

suboceanic (adjective)	marine (adjective)
formed or situated or occurring beneath the ocean or the ocean bed	relating to or characteristic of or occurring on or in the sea
	of or relating to the sea
	of or relating to military personnel who serve both on land and at sea (specifically the U.S. Marine Corps)
	relating to or involving ships or shipping or navigation or seamen
	native to or inhabiting the sea