marine

American  

[muh-reen] / məˈrin /

adjective

1. of or relating to the sea; existing in or produced by the sea.

   marine vegetation.

2. pertaining to navigation or shipping; nautical; naval; maritime.

3. serving on shipboard, as soldiers.

4. of or belonging to the marines.

5. adapted for use at sea.

   a marine barometer.

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noun

1. a member of the U.S. Marine Corps.

2. one of a class of naval troops serving both on shipboard and on land.

3. seagoing ships collectively, especially with reference to nationality or class; shipping in general.

4. a picture with a marine subject; seascape.

5. naval affairs, or the department of a government, as in France, having to do with such affairs.

idioms

1. dead marine, an empty bottle of beer or spirits.

2. tell it / that to the marines! I don't believe your story; I refuse to be fooled.

marine British  

/ məˈriːn /

adjective

1. of, found in, or relating to the sea

2. of or relating to shipping, navigation, etc

3. of or relating to a body of seagoing troops

   marine corps

4. of or relating to a government department concerned with maritime affairs

5. used or adapted for use at sea

   a marine camera

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noun

1. shipping and navigation in general

   the merchant marine

2. (capital when part of a name) a member of a marine corps or similar body

3. a picture of a ship, seascape, etc

4. informal an expression of disbelief

marine Scientific  

/ mə-rēn′ /

1. Relating to the sea.

2. Relating to a system of open-ocean and unprotected coastal habitats, characterized by exposure to wave action, tidal fluctuation, and ocean currents and by the absence of trees, shrubs, or emergent vegetation. Water in the marine system is at or near the full salinity of seawater.

3. Compare lacustrine palustrine riverine

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Other Word Forms

• intermarine
  adjective
• nonmarine
  adjective
• semimarine
  adjective
• supermarine
  adjective
• unmarine
  adjective

Etymology

Origin of marine

1325–75; Middle English maryne < Middle French marin (feminine marine ) < Latin marīnus of the sea, derivative of mare sea; see -ine ¹

Explanation

If it has to do with the ocean or sea, you can call it marine. Your friend in the U.S. 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.

Example Sentences

Scientists have identified a massive new species of mosasaur, a marine reptile that lived alongside the dinosaurs and dominated prehistoric oceans.

From Science Daily • May 23, 2026

Ms. Jackson, a marine biologist and science educator, includes brief informational tidbits about the species we’re on the lookout for, with an eye for details that will appeal to the sensibilities of curious readers.

From The Wall Street Journal • May 22, 2026

The Italian divers included a marine biology professor with many years of experience, her daughter, two young researchers, and their Maldives-based guide.

From Barron's • May 21, 2026

Leising said he expects the current marine heat wave, which would typically start fading sometime between October and December, to instead be prolonged by the arrival of warmer oceanic waters from El Niño.

From Los Angeles Times • May 14, 2026

Lizards challenged lizards while people watched, and marine iguanas walked between human feet on their way down the beaches to feed in the sea.

From "Frightful's Mountain" by Jean Craighead George

Related Words

• aquatic
• coastal
• deep-sea
• maritime
• naval
• saltwater
• seagoing