1.Definition: native to or inhabiting the sea
"Marine plants and animals such as seaweed and whales"
2.Definition: of or relating to military personnel who serve both on land and at sea (specifically the U.S. Marine Corps)
3.Definition: of or relating to the sea
4.Definition: relating to or characteristic of or occurring on or in the sea
5.Definition: relating to or involving ships or shipping or navigation or seamen