offshore vs marine

offshore is not a noun while marine is a noun.

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

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

offshore (adjective)	marine (adjective)
(of winds) coming from the land	relating to or characteristic of or occurring on or in the sea
at some distance from the shore	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

offshore (adverb)	marine (adverb)
away from shore; away from land