Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine geology. As a noun it can be a term for a certain kind of navy, or those enlisted in such a navy. In scientific contexts, the term almost always refers exclusively to saltwater environments, although in other contexts (e.g., engineering) it may refer to any (usually navigable) body of water.
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