If it has to do with the ocean or sea, you can call it marine. Your friend in US Armed Services who is a Marine probably spends a lot of time near the ocean.

Marine life is everything that lives in the water: plants, fish, sharks, algae, crabs, seahorses, giant squid, and the list goes on and on. When you study things that live in or near the sea, you are either a marine biologist or just really excited about ocean life. If you work in a field that deals with the ocean, boats, sailors or the navy you could be, for instance, a marine meteorologist.

Definitions of marine

adj of or relating to the sea

marine explorations”

adj relating to or characteristic of or occurring on or in the sea

of or taking place in the deeper parts of the sea
oceangoing, seafaring, seagoing
used on the high seas
constituting or living in the open sea
at some distance from the shore
oversea, overseas
being or passing over or across the sea
subocean, suboceanic
formed or situated or occurring beneath the ocean or the ocean bed

adj native to or inhabiting the sea

marine plants and animals such as seaweed and whales”
operating or living or growing in water

adj relating to or involving ships or shipping or navigation or seamen

marine insurance”
maritime, nautical

adj of or relating to military personnel who serve both on land and at sea (specifically the U.S. Marine Corps)

marine barracks”

n a soldier who serves both on shipboard and on land

Type of:
an enlisted man or woman who serves in an army

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