The Collaborative International Dictionary of English v.0.48:

Barkentine \Bark"en*tine\, n. [See Bark, n., a vessel.]
   (Naut.)
   A threemasted vessel, having the foremast square-rigged, and
   the others schooner-rigged. [Spelled also barquentine,
   barkantine, etc.] See Illust. in Append.
   [1913 Webster]