is an umbrella term
. As an adjective it is usually applicable to things relating to the sea
, such as marine biology
, marine ecology 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.