Ma·rine, n.
  1. A solider serving on shipboard; a sea soldier; one of a body of troops trained to do duty in the navy.
  3. The sum of naval affairs; naval economy; the department of navigation and sea forces; the collective shipping of a country; as, the mercantile marine.
  4. A picture representing some marine subject.
  Tell that to the marines, an expression of disbelief, the marines being regarded by sailors as credulous. [Colloq.]
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