As an English term, Marine covers as an adjective several aspects relating to the sea or ocean, mostly saltwater. However in the engineering context it refers to any body of water.

 

A Marine as a person is a soldier usually involved in naval operations.

The Marine describes the whole fleet of a Nation, unusual in English but common used in other languages like Dutch and German.

German: Die Marine (English: Navybeschreibt das Seewesen eines Staates (Handelsmarine, Kriegsmarine) Im engeren Sinne beschreibt sie alles, was mit dem seemännischen Teil des Militärs zu tun hat (Flotte, Seeleute, militärische Häfen und Stützpunkte)


List of books: Marine