merchantman

from WordNet (r) 3.0 (2006)

merchantman
    n 1: a cargo ship; "they did much of their overseas trade in
         foreign bottoms" [syn: {bottom}, {freighter},
         {merchantman}, {merchant ship}]

from The Collaborative International Dictionary of English v.0.48

Merchantman \Mer"chant*man\, n.; pl. {Merchantmen}.
   [1913 Webster]
   1. A merchant. [Obs.] --Matt. xiii. 45.
      [1913 Webster]

   2. A trading vessel; a ship employed in the transportation of
      goods, as, distinguished from a man-of-war.
      [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

MERCHANTMAN. A ship or vessel employed in a merchant's service. This term is 
used in opposition to a ship of war.

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