[1] : The Collaborative International Dictionary of English v.0.48

seaman \sea"man\, n.; pl. seamen. as. saeman.
   one whose occupation is to assist in the management of ships
   at sea; a mariner; a sailor; -- applied both to officers and
   common mariners, but especially to the latter. opposed to
   landman, or landsman.
   1913 webster

   able seaman, a sailor who is practically conversant with
      all the duties of common seamanship.

   ordinary seaman. see ordinary.
      1913 webster
see also:
seamen landman landsman able seaman ordinary seaman ordinary 

[2] : WordNet (r) 2.0

able seaman
     n : a seaman in the merchant navy; trained in special skills
         syn: able-bodied seaman
see also:
able-bodied seaman 

Able >> A Words
Able, definition of term: Able
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