mainsheet

from WordNet (r) 3.0 (2006)

mainsheet
    n 1: (nautical) a line (rope or chain) that regulates the angle
         at which a sail is set in relation to the wind [syn:
         {sheet}, {tack}, {mainsheet}, {weather sheet}, {shroud}]

from The Collaborative International Dictionary of English v.0.48

mainsheet \main"sheet`\, n. (Naut.)
   One of the ropes by which the mainsail is hauled aft and
   trimmed.
   [1913 Webster]

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