Source : Webster's Revised Unabridged Dictionary (1913)

Masted \Mast"ed\, a.
   Furnished with a mast or masts; -- chiefly in composition;
   as, a three-masted schooner.

Mast \Mast\, v. t. [imp. & p. p. {Masted}; p. pr. & vb. n.
   {Masting}.]
   To furnish with a mast or masts; to put the masts of in
   position; as, to mast a ship.

Source : WordNet®

masted
     adj : having or furnished with a mast; often used in combination;
           "probably was so masted when she set forth"-
           S.E.Morrison; "a three-masted bark"