1. [n]  a member of the United States Marine Corps
2. [adj]  native to or inhabiting the sea; "marine plants and animals such as seaweed and whales"; "saltwater fish"
3. [adj]  of or relating to the sea; "marine explorations"
4. [adj]  of or relating to military personnel who serve both on land and at sea (specifically the U.S. Marine Corps); "marine barracks"
5. [adj]  relating to or involving ships or shipping or navigation or seamen; "nautical charts"; "maritime law"; "marine insurance"

Marine
Clancy presents an insider`s view of the Marine Corps. This book includes an interview with the Commandant of the Marine Corps, General Charles Krulak, an overview of the tools and technology of the Marine Expeditionary Unit, and an in-depth look at recruitment and training.

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1. \Ma*rine"\, a. [L. marinus, fr. mare the sea: cf. F.
   marin. See {Mere} a pool.]
   1. Of or pertaining to the sea; having to do with the ocean,
      or with navigation or naval affairs; nautical; as, marine
      productions or bodies; marine shells; a marine engine.
   2. (Geol.) Formed by the action of the currents or waves of
      the sea; as, marine deposits.
   {Marine acid} (Chem.), hydrochloric acid. [Obs.]
   {Marine barometer}. See under {Barometer}.
   {Marine corps}, a corps formed of the officers,
      noncommissioned officers, privates, and musicants of
      marines.
   {Marine engine} (Mech.), a steam engine for propelling a
      vessel.
   {Marine glue}. See under {Glue}.
   {Marine insurance}, insurance against the perils of the sea,
      including also risks of fire, piracy, and barratry.
   {Marine interest}, interest at any rate agreed on for money
      lent upon respondentia and bottomry bonds.
   {Marine law}. See under {Law}.
   {Marine league}, three geographical miles.
   {Marine metal}, an alloy of lead, antimony, and mercury, made
      for sheathing ships. --Mc Elrath.
   {Marine soap}, cocoanut oil soap; -- so called because, being
      quite soluble in salt water, it is much used on shipboard.
   {Marine store}, a store where old canvas, ropes, etc., are
      bought and sold; a junk shop. [Eng.]
   

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